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For 1990-2009 cars only

Powertrain Control Module Scan Tool Information 3.8L

Table 1: Powertrain Control Module Scan Tool Data Parameters
Table 2: Powertrain Control Module Scan Tool Output Controls

The Engine Control Module Scan Tool Data List contains all engine-related parameters that are available on the scan tool. The list is arranged in alphabetical order. A given parameter may appear in any one of the data lists, and in some cases may appear more than once, or in more than one data list in order to group certain related parameters together.

Use the Engine Scan Tool Data List only after the following is determined:

    • The Diagnostic System Check - Vehicle is completed.
    • No diagnostic trouble codes (DTCs)
    • On-board diagnostics are functioning properly

The scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents values that would be seen on a normally running engine.

Important: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis. If all values are within the typical range described below, refer to for diagnosis.

Powertrain Control Module Scan Tool Data Parameters

Parameter

System State

Expected Value

Description

Base Operating Conditions: Engine Idling/Radiator Hose Hot/Closed Throttle/Park or Neutral/Closed Loop/Accessories Off/Brake Pedal Released

1-2 Sol. Ckt Status

--

OK

This parameter displays the solenoid valve feedback voltage signal circuit status on the scan tool. If the voltage is low when the solenoid is commanded OFF, the scan tool will display Open/Short to GND. If the voltage is high when the solenoid is commanded ON, the scan tool will display Short to Volts. If no circuit fault is present, the scan tool will display OK. Until the circuit has been evaluated, the scan tool will display Indeterminate.

2-3 Sol. Ckt Status

--

OK

This parameter displays the solenoid valve feedback voltage signal circuit status on the scan tool. If the voltage is low when the solenoid is commanded OFF, the scan tool will display Open/Short to GND. If the voltage is high when the solenoid is commanded ON, the scan tool will display Short to Volts. If no circuit fault is present, the scan tool will display OK. Until the circuit has been evaluated, the scan tool will display Indeterminate.

1-2 Shift Error

--

0.00 Seconds

This parameter displays the difference between the desired 1-2 shift time and the actual 1-2 shift time. A positive number indicates a firm or fast shift, the actual shift time was shorter than the desired shift time. A negative number indicates a soft or slow shift, the actual shift time was longer than the desired shift time. This value is only accurate if the shift was adaptable.

2-3 Shift Error

--

0.00 Seconds

This parameter displays the difference between the desired 2-3 shift time and the actual 2-3 shift time. A positive number indicates a firm or fast shift, the actual shift time was shorter than the desired shift time. A negative number indicates a soft or slow shift, the actual shift time was longer than the desired shift time. This value is only accurate if the shift was adaptable.

3-4 Shift Error

--

0.00 Seconds

This parameter displays the difference between the desired 3-4 shift time and the actual 3-4 shift time. A positive number indicates a firm or fast shift, the actual shift time was shorter than the desired shift time. A negative number indicates a soft or slow shift, the actual shift time was longer than the desired shift time. This value is only accurate if the shift was adaptable.

1-2 Shift Time

--

0.00 Seconds

This parameter displays the actual time of the last adaptable 1-2 shift. The shift time is based on the gear ratio change after the commanded 1-2 shift.

2-3 Shift Time

--

0.00 Seconds

This parameter displays the actual time of the last adaptable 2-3 shift. The shift time is based on the gear ratio change after the commanded 2-3 shift.

3-4 Shift Time

--

0.00 Seconds

This parameter displays the actual time of the last adaptable 3-4 shift. The shift time is based on the gear ratio change after the commanded 3-4 shift.

1-2 Sol.

--

On

This parameter displays the commanded state of the 1-2 shift solenoid valve. When the transmission is in FIRST and FOURTH gear, the display should indicate ON, current is flowing trough the solenoid. When the transmission is in SECOND and THIRD gear, the display should indicate OFF, current is not flowing through the solenoid.

2-3 Sol.

--

On

This parameter displays the commanded state of the 2-3 shift solenoid valve. When the transmission is in FIRST and SECOND gear, the display should indicate ON, current is not flowing trough the solenoid. When the transmission is in THIRD and FOURTH gear, the display should indicate OFF, current is flowing through the solenoid.

1-2 TAP Cell 4-16

--

Varies

This parameter displays the amount of transmission adaptive pressure (TAP), based on 17 N·m (12.5 lb ft) of engine torque increment per cell, added to or subtracted from shift pressure during a 1-2 upshift. A positive number indicates that long shifts have been detected and PC solenoid pressure has been added in order to decrease shift time. A negative number indicates that short shifts have been detected and PC solenoid pressure has been subtracted in order to increase shift time.

2-3 TAP Cell 4-16

--

Varies

This parameter displays the amount of transmission adaptive pressure (TAP), based on 17 N·m (12.5 lb ft) of engine torque increment per cell, added to or subtracted from shift pressure during a 2-3 upshift. A positive number indicates that long shifts have been detected and PC solenoid pressure has been added in order to decrease shift time. A negative number indicates that short shifts have been detected and PC solenoid pressure has been subtracted in order to increase shift time.

3-4 TAP Cell 4-16

--

Varies

This parameter displays the amount of transmission adaptive pressure (TAP), based on 17 N·m (12.5 lb ft) of engine torque increment per cell, added to or subtracted from shift pressure during a 3-4 upshift. A positive number indicates that long shifts have been detected and PC solenoid pressure has been added in order to decrease shift time. A negative number indicates that short shifts have been detected and PC solenoid pressure has been subtracted in order to increase shift time.

A/C Disengage 1-4 History

--

Varies

This parameter displays the reason for A/C disengagement including: None, A/C Pressure, Engine Speed, Battery Voltage, Stall Prevention, RPM Unstable, Wide Open Throttle (WOT), Launch Performance, and Coolant Hot.

A/C Clutch Feedback Signal

--

Relay Off

This parameter displays the commanded state of the air conditioning (A/C) compressor clutch relay driver circuit and displays On or Off. The A/C compressor clutch should be engaged when On displays. When the display indicates On, the line pressure and the shift times will be adjusted for the additional engine load.

A/C High Side Pressure Sensor

--

835 kPa (121 psi)

Varies

This parameter shows the high side A/C refrigerant pressure.

A/C High Side Pressure Sensor

--

1.41 Volts

Varies

This parameter shows the high side A/C refrigerant pressure, displayed in volts.

A/C Off For WOT

--

No

This parameter shows wether the reason for A/C disengagement was for a wide open throttle (WOT) event.

A/C Pressure Disable

--

No

The scan tool displays Yes or No. Yes is displayed when the system pressure exceeds 3,034 kPa (440 psi).

A/C Relay Circuit History

--

OK

Scan tool displays OK, Open, Short, or Invalid State. Indicates the diagnostic state of the A/C relay control circuit.

A/C Relay Circuit Status

--

OK

Scan tool displays OK, Fault, or Invalid State. Indicates the diagnostic state of the A/C relay control circuit.

A/C Relay Command

--

Off

The scan tool displays ON or OFF. ON is displayed when the ECM has energized the A/C compressor clutch relay.

With A/C Selected

On

A/C Request Signal

--

No

The scan tool displays Yes or No. Yes is displayed when the HVAC control module is requesting A/C operation.

With A/C Selected

Yes

AIR Indicated Pressure

--

0.00 kPa

This parameter displays the normalized secondary air injection system pressure. The normalized pressure is the filtered pressure minus the ambient air pressure measured by the sensor.

AIR Monitor Complete This Ignition

--

Yes

This parameter displays the completion status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include: Yes or No.

AIR Monitor Enabled This Ignition

--

No

This parameter displays the enable status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include: Yes or No.

AIR Pressure Sensor

--

Same as BARO

This parameter displays the unfiltered secondary air injection system pressure.

AIR Pressure Sensor

--

2.51 Volts

Varies

This parameter displays the secondary air injection system pressure analog input as a voltage.

AIR Pump Relay Command

--

OFF

This parameter displays the commanded state of the secondary air injection pump. The states include: On or Off.

AIR Solenoid Command

--

OFF

This parameter displays the commanded state of the secondary air injection valve. The states include: On or Off.

AIR Test Result

--

Passed

This parameter indicates the result of the secondary air injection (SAI) diagnostic test. The results include Test Running, Aborted, Passed, Failed-DTC Set, No Result, or Error.

AIR Test State

--

Result Avail.

This parameter indicates the current state of the secondary air injection (SAI) diagnostic. These states displayed are Test Disabled, Phase 1, Phase 2, Phase 3, Result Available, Test Completed.

APP Indicated Angle

Accelerator pedal not depressed

0%

This parameter displays the angle of the accelerator pedal as calculated by the PCM using the signals from the accelerator pedal position sensors. The APP indicated angle is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.

Accelerator pedal fully depressed

100%

APP Sensor 1

Accelerator pedal not depressed

0.82 Volts

This parameter displays the voltage signal sent to the PCM from accelerator pedal position (APP) sensor 1 of the APP sensor assembly. APP sensor 1 is a range of values indicating a low voltage when the accelerator pedal is not depressed to a high voltage when the accelerator pedal is fully depressed.

Accelerator pedal fully depressed

3.90 Volts

APP Sensor 1 and 2

--

Agree

This parameter displays the results of a PCM test that compares the signals from the APP sensors 1 and 2. The scan tool will display Agree or Disagree. Agree indicates that APP sensor 1 and APP sensor 2 voltages correspond to the same accelerator pedal position. Disagree indicates that APP sensor 1 and APP sensor 2 voltages correspond to different accelerator pedal positions.

APP Sensor 1 Circuit Status

--

OK

This parameter indicates the diagnostic test state of the accelerator pedal position (APP) sensor 1 circuit. The scan tool displays OK or Fault.

APP Sensor 1 Indicated Position

Accelerator pedal not actuated

0%

This parameter displays the position of the APP sensor 1 as calculated by the control module using the signal from the APP sensor 1. APP sensor 1 is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.

Accelerator pedal fully actuated

100%

APP Sensor 2

Accelerator pedal not depressed

1.02 Volts

This parameter displays the voltage signal sent to the PCM from accelerator pedal position (APP) sensor 2 of the APP sensor assembly. APP sensor 2 is a range of values indicating a low voltage when the accelerator pedal is not depressed to a high voltage when the accelerator pedal is fully depressed.

Accelerator pedal fully depressed

4.02 Volts

APP Sensor 2 Circuit Status

--

OK

This parameter indicates the diagnostic test state of the accelerator pedal position (APP) sensor 2 circuit. The scan tool displays OK or Fault.

APP Sensor 2 Indicated Position

Accelerator pedal not actuated

0%

This parameter displays the angle of the APP sensor 2 as calculated by the control module using the signal from the APP sensor 2. APP sensor 2 is a range of values indicating a low percentage when the accelerator pedal is not depressed to a high percentage when the accelerator pedal is fully depressed.

Accelerator pedal fully actuated

100%

BARO

--

60-104 kPa (varies with altitude)

This parameter displays the barometric pressure as calculated by the PCM using the signal from the manifold absolute pressure (MAP) sensor measured when the ignition is turned on with the engine not running. The control module will also update the barometric pressure during wide-open throttle (WOT) conditions.

BPP Circuit Signal

--

Inactive

The scan tool displays Active or Inactive. This parameter shows the position of the brake pedal position sensor through the stop lamp switch signal circuit.

Brake pedal depressed

Active

Catalyst Monitor Complete This Ignition

--

No

This parameter displays the monitor completion status during the current driving/monitoring cycle.

Catalyst Monitor Enabled This Ignition

--

Yes

This parameter displays the monitor enable status during the current driving/monitoring cycle.

Catalytic Converter Protection Active

--

No

This parameter displays the state of the Catalytic Converter Protection mode.

Change Engine Oil Indicator Command

--

OFF

The scan tool displays ON or OFF. This is the state of the Change Engine Oil indicator as commanded by the PCM.

Cmmd. A/F Equivalence Ratio

--

1.0:1

Equivalence numbers greater than one represent excess fuel in the fuel air mix. Equivalence numbers less than one represent a deficiency of fuel in the fuel air mix for complete combustion. The equivalence ratio will be reported as one when the vehicle is in Closed Loop.

CMP Sensor

--

Same as engine speed

This parameter displays the speed of the engine as calculated by the signal from the CMP sensor.

CMP Sensor Signal Present

--

Yes

Camshaft position (CMP) Sensor Signal Present indicates if the PCM is receiving the cam sensor reference signal from the ignition control module (ICM). The scan tool displays Yes or No.

Commanded Gear

--

1

This parameter displays the current commanded state of the shift solenoid valves. The scan tool displays 1, 2, 3, 4 or 5.

Crank Request Signal

--

No

This parameter shows the power mode status of the starter motor. When Yes is displayed, a request to engage the starter has been received by the PCM.

Crankshaft Position Sensor A

--

Same as engine speed

This parameter represents the reference pulses received from the ignition control module (ICM) on the 3X low resolution engine speed signal circuit.

Crankshaft Position Sensor B

--

Same as engine speed

This parameter represents the reference pulses received from the ignition control module (ICM) on the 18X medium resolution engine speed signal circuit.

Cruise

--

Disabled

This parameter displays the commanded state of the cruise control system. The scan tool displays ENABLED or DISABLED. When the display indicates ENABLED, the PCM is allowing cruise control operation. When the display indicates DISABLED, the PCM has disabled cruise control operation. When the cruise control display is ENABLED, shift patterns will be altered for 2-3 and 3-4 upshifts or 4-3 and 3-2 downshifts.

Cruise Control Active

--

No

This parameter displays the status of the cruise control system as determined by the PCM. The scan tool will display Yes when the cruise control system is in control of vehicle speed. The scan tool will display No when the cruise control system is not operating.

Cruise On/Off Switch

--

Off

The scan tool displays ON or OFF. This is the state of the switch as monitored by the body control module (BCM).

Switch pressed

On

Cruise Resume/Accel Switch

--

Inactive

The scan tool displays Active or Inactive. This is the state of the switch as monitored by the body control module (BCM).

Switch pressed

Active

Cruise Set/Coast Switch

--

Inactive

The scan tool displays Active or Inactive. This is the state of the switch as monitored by the body control module (BCM).

Switch pressed

Active

Current TAP Cell

--

2

This parameter displays the current transmission adaptive pressure (TAP) cell in use for transmission line pressure adaptation. The cells are based on 17 N·m (12.5 lb ft) of engine torque. The higher the engine torque, the higher the current TAP cell. The last cell used will remain displayed until the next adaptable upshift occurs.

Cycles of Misfire Data

--

0-100 Counts incrementing

This parameter displays the number of cylinder firing events that were recorded as misfires as determined by the control module.

Cylinder 1 and 4 IC Circuit Status

--

OK

This parameter displays the status of the output driver for the ignition control circuit. The scan tool will display OK if the circuit is operating correctly or Fault if there is a short to ground, open, or a short to voltage on the circuit.

Cylinder 1-6 Injector Circuit History

--

OK

Scan Tool displays OK, Open, Short, or Invalid. This parameter saves the state of the driver circuit for this device.

Cylinder 1-6 Injector Circuit Status

--

OK

This parameter displays the current status of the output driver for the fuel injector control circuit. The scan tool will display OK if the circuit is operating correctly or Incomplete if a diagnosis has not been made. The scan tool will display Short Gnd, if there is a short to ground, Open, if there is an open, Short to B+ if there is a short to voltage on the circuit.

Cylinder 2 and 5 IC Circuit Status

--

OK

This parameter displays the status of the output driver for the ignition control circuit. The scan tool will display OK if the circuit is operating correctly or Fault if there is a short to ground, open, or a short to voltage on the circuit.

Cylinder 3 and 6 IC Circuit Status

--

OK

This parameter displays the status of the output driver for the ignition control circuit. The scan tool will display OK if the circuit is operating correctly or Fault if there is a short to ground, open, or a short to voltage on the circuit.

Decel. Fuel Cutoff

--

Inactive

This parameter displays the status of the operating mode used to turn off the fuel injectors during certain deceleration conditions. When the scan tool displays Active, the PCM has turned off the fuel injectors. When the scan tool displays Inactive, the fuel system is operating normally.

Desired EGR Position

--

0%

Scan tool displays volts or a range from 0-100 percent. Represents the exhaust gas recirculation (EGR) pintle position that the PCM is commanding. Desired EGR Position should stay close to EGR position sensor.

Desired Idle Speed

--

720 RPM

This parameter displays the engine idle speed in RPM commanded by the control module. The control module compensates for various engine loads in order to maintain the desired engine RPM at idle. This parameter is not valid unless the engine is running.

Distance Since DTC Cleared

--

Varies

This parameter displays the distance accumulated since an emission diagnostic trouble code was cleared. The scan tool will display increasing distance as the vehicle is driven.

Driver Module 1 Status

--

Enabled

Driver Module 1 Status indicates the diagnostic state of the module. The scan tool displays Enabled, Off-High Volts, Off-High Temp, or Invalid State.

Driver Module 2 Status

--

Enabled

Driver Module 2 Status indicates the diagnostic state of the module. The scan tool displays Enabled, Off-High Volts, Off-High Temp, or Invalid State.

Driver Module 3 Status

--

Enabled

Driver Module 3 Status indicates the diagnostic state of the module. The scan tool displays Enabled, Off-High Volts, Off-High Temp, or Invalid State.

EC Ignition Relay Circuit History

--

OK

Indicates the diagnostic state of output driver for the EC ignition relay control circuit. The scan tool displays OK, Open, Short, or Invalid State.

EC Ignition Relay Circuit Status

--

OK

This parameter displays the status of the output driver for the engine control (EC) ignition relay control circuit. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is a short to ground, open, or a short to voltage on the circuit.

ECT Sensor

--

95°C/203°F

105°C/221°F

This parameter displays the temperature of the engine coolant based on the input from the engine coolant temperature sensor. When the coolant temperature is low, the scan tool will display a low temperature. When the coolant temperature is high, the scan tool will display a high temperature.

EGR Flow Test Count

--

0

Scan tool range 0-255. Indicates the number of EGR flow test samples collected during the current ignition cycle. The maximum number of samples allowed is 1 during normal operation. If the PCM battery feed has been disconnected or a DTC P0401 has been cleared, several EGR flow test samples will be allowed during the next ignition cycle. This is to allow repair verification during a single ignition cycle.

EGR Learned Minimum Position

--

0.13 Volts

Scan tool range 0.0-5.0 volts. Represents the learned voltage that the PCM uses to determine whether or not the EGR valve is fully closed, 0 percent pintle position. If the Desired EGR Position is 0 percent and a difference of more than 0.4 volt between EGR Feedback and EGR Closed Valve Pintle Position is detected, the PCM will illuminate the MIL to indicate an EGR system fault.

EGR Monitor Complete This Ignition

--

No

This parameter displays the completion status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include: Yes or No.

EGR Monitor Enabled This Ignition

--

Yes

This parameter displays the enable status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include: Yes or No.

EGR Position Sensor

--

0%

Scan tool range 0-100 percent. Represents the actual position of the EGR pintle in percent. 0 percent displayed indicates a fully extended pintle, the EGR valve is closed.

EGR Position Sensor

--

0.51 Volts

Scan tool range 0.00-5.00 volts. Indicates the EGR pintle position sensor signal voltage being monitored by the PCM. A low voltage indicates a fully extended pintle, closed valve, a voltage near 5 volts indicates a fully retracted pintle, open valve.

EGR Position Variance

--

0%

Scan tool range 0-100 percent. Indicates the difference between Desired EGR Position and Actual EGR Position currently being monitored by the PCM. If the EGR Position Variance reaches an unacceptable level, the PCM will illuminate the MIL to indicate an EGR system fault.

EGR Solenoid Circuit History

--

OK

EGR Solenoid Circuit History indicates the diagnostic state of the output driver for the EGR solenoid circuit. The scan tool displays OK, Open, Stuck Low, Stuck High, High Voltage, High Temp, or Invalid State.

EGR Solenoid Circuit Status

--

OK

EGR Solenoid Circuit Status indicates the diagnostic state of the output driver for the EGR solenoid circuit. The scan tool displays Fault, OK or Invalid State.

EGR Solenoid Command

--

0%

Scan tool range 0-100 percent. Represents the EGR valve driver pulse width modulation (PWM) signal from the PCM. A duty cycle of 0 percent indicates that no EGR flow is being commanded, a 100 percent duty cycle indicates maximum EGR flow commanded.

Engine Hot Lamp Command

--

Off

This parameter displays the commanded state of the engine hot lamp.

Engine Load

--

Varies with Altitude

This parameter displays the engine load in percent based on inputs to the control module from various engine sensors. The scan tool will display a low percentage when the engine is at idle with little or no load. The scan tool will display a high percentage when the engine is running at a high RPM under a heavy load.

Engine Oil Level Switch

--

OK

This parameter indicates if the Engine oil level is OK or Low.

Engine Oil Life Remaining

--

Varies

This parameter indicates the percentage of time left before an oil change is necessary according to the oil life monitor.

Engine Oil Pressure Switch

--

OK

This parameter displays the state of the engine oil pressure as determined by the PCM. The PCM monitors the engine oil pressure switch to determine if the engine oil pressure is sufficient. The scan tool will display low when the engine oil pressure is below a predetermined value.

The scan tool displays OK or Low. This parameter displays whether or not sufficient engine oil pressure is present.

Engine Run Time

--

Varies

This parameter displays the time elapsed since the engine was started. The scan tool will display the time in hours, minutes and seconds. The engine run time will reset to zero when the engine stops running.

Engine Speed

--

700-800 RPM

This parameter displays the speed of the crankshaft as determined by the control module using an input from the crankshaft position (CKP) sensor. The scan tool will display a high value at high engine speeds and a low value at low engine speeds.

Engine Speed Circuit Status

--

OK

This parameter indicates the diagnostic test state of the engine speed circuit. The scan tool displays OK or Fault.

Engine Torque

--

10-20 ft lbs

This parameter displays a calculated value based on engine load, throttle position, mass air flow, and other engine inputs. This parameter is accurate to within 20 N·m (15 ft lb) of actual measured engine torque.

EVAP Fault History

--

No Fault

This parameter displays the result of the evaporative emission (EVAP) system diagnostic.

Scan tool displays NO FAULT, EXCESS VACUUM, PURGE VALVE LEAK, SMALL LEAK, WEAK VACUUM, or NO TEST RESULT. The EVAP Fault History indicates the status of EVAP system diagnostics performed by the PCM.

EVAP Monitor Complete This Ignition

--

No

This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

EVAP Monitor Enabled This Ignition

--

No

This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.

EVAP Purge Solenoid Circuit History

--

OK

Evaporative emission (EVAP) Purge Solenoid Circuit History indicates the diagnostic state of the output driver for the EVAP purge solenoid circuit. The scan tool displays OK, Open, Short, or Invalid State.

EVAP Purge Solenoid Circuit Status

--

OK

This parameter displays the status of the output driver for the evaporative emission purge solenoid control circuit. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

EVAP Purge Solenoid Command

--

10-20%

This parameter displays the on-time or duty cycle of the EVAP purge solenoid commanded by the PCM expressed as a percent. The scan tool will display a high percentage when the PCM is commanding the EVAP purge solenoid to be open a large amount. The scan tool will display a low percentage when the control module is commanding the EVAP purge solenoid to be open a small amount. The scan tool will display 0 when the PCM is commanding the EVAP purge solenoid closed.

EVAP Vent Solenoid Circuit History

--

OK

EVAP Vent Solenoid Circuit History indicates the diagnostic state of the output driver for the EVAP vent solenoid circuit. The scan tool displays Fault, OK or Invalid.

EVAP Vent Solenoid Circuit Status

--

OK

This parameter displays the status of the output driver for the evaporative emission vent solenoid control circuit. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

EVAP Vent Solenoid Command

--

Venting

This parameter displays the state of the EVAP vent solenoid commanded by the PCM expressed as a Venting or Not Venting. The scan tool will display a venting when the control module is commanding the EVAP vent solenoid to be open. The scan tool will display a not venting when the control module is commanding the EVAP vent solenoid to be closed.

FC Relay 1 Circuit History

--

OK

Relay 1 Circuit History indicates the diagnostic state of the output driver for the FC relay 1 circuit. The scan tool displays OK, Open, Short, or Invalid.

FC Relay 1 Circuit Status

--

OK

Relay 1 Circuit Status indicates the diagnostic state of the output driver for the FC relay 1 circuit. The scan tool displays Fault, OK or Invalid State.

FC Relay 1 Command

--

Off

FC relay 1 Command indicates the commanded state of the FC relay 1. The scan tool displays ON or OFF.

FC Relays 2 and 3 Circuit History

--

OK

FC Relay 2 and 3 Circuit History indicates the diagnostic state of the output driver for the FC relay 2 and 3 circuits. The scan tool displays OK, Open, Short, or Invalid.

FC Relays 2 and 3 Circuit Status

--

OK

FC Relay 2 and 3 Circuit Status indicates the diagnostic state of the output driver for the FC relay 2 and 3 circuits. The scan tool displays Fault, OK or Invalid State.

FC Relays 2 and 3 Command

--

Off

FC Relay 2 and 3 Command indicates the commanded state of the FC relays 2 and 3. The scan tool displays ON or OFF.

Fuel Level Sensor

--

Varies

This parameter displays the approximate fuel level in the fuel tank as a voltage. The PCM calculates this level using the signal from the sensor used to monitor the fuel level in the fuel tank. The scan tool will display a low reading when the fuel level in the tank is low or near empty. The scan tool will display a high reading when the fuel level in the tank is high or near full.

Fuel Pump Relay Circuit History

--

OK

Fuel Pump Relay Circuit History indicates the diagnostic state of the output driver for the fuel pump relay control circuit. The scan tool displays OK, Open, Stuck Low, Stuck High, High Voltage, High Temp, or Invalid.

Fuel Pump Relay Circuit Status

--

OK

This parameter displays the status of the output driver for the fuel pump relay control circuit. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

Fuel Pump Relay Command

--

On

This parameter displays the commanded state of the fuel pump relay control circuit. The fuel pump relay should be on when the scan tool indicates the Fuel Pump Relay Command is On. The fuel pump relay should be off when the scan tool indicates the Fuel Pump Relay Command is Off.

Fuel Tank Level Remaining

--

Varies

This parameter displays the amount of fuel remaining in the fuel tank as a percentage. The PCM calculates this level using the signal from the sensor used to monitor the fuel level in the fuel tank. The scan tool will display a low reading when the fuel level in the tank is low or near empty. The scan tool will display a high reading when the fuel level in the tank is high or near full.

Fuel Tank Pressure Sensor

--

-19.8 to +12.52 mm Hg/-10.5 to +6.17 in H2O

This parameter displays the fuel tank pressure as calculated based on a signal sent to the PCM from the fuel tank pressure (FTP) sensor. The scan tool will display a low value when the pressure in the fuel tank is low or a vacuum. The scan tool will display a high value when the pressure in the fuel tank is high.

Fuel Trim Cell

--

0

This parameter displays the fuel trim cell number as calculated by the control module based on engine speed and load inputs. The scan tool will display a lower number as conditions are nearer to idle, and a higher value as conditions approach maximum engine speed and maximum load.

Fuel Trim Learn

--

Enabled

This parameter indicates if the PCM is adjusting long term fuel trim in response to the short term fuel trim. The scan tool displays Enabled or Disabled. When conditions are appropriate for enabling long term fuel trim corrections, the scan tool displays Enabled.

Gear Ratio

--

3.98:1

This parameter displays the actual transmission gear ratio. The scan tool displays the gear ratio calculated from the automatic transmission input shaft speed sensor (AT ISS) and the automatic transmission output shaft speed sensor (AT OSS) inputs.

GEN F-Terminal Signal

--

38%

Varies with electrical load

This parameter is a PCM input of the generator field duty cycle. This is an indication of generator load on the engine.

GEN L-Terminal Signal Command

--

On

This parameter indicates the generator commanded state by the PCM.

Generator Lamp Command

--

Off

This parameter displays the commanded state of the generator lamp.

HO2S 1

--

0-1,000 mV

Represents the fuel control exhaust oxygen sensor (O2S) output voltage. Should fluctuate constantly within a range between 10 mV, lean exhaust, and 1,000 mV, rich exhaust, while operating in Closed Loop.

HO2S 1 Heater

--

0.82 Amps

Varies

This parameter displays the current through the control module when the HO2S heater is commanded ON by the control module. HO2S Heater Sen. 1 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S 1 Heater Circuit History

--

OK

The HO2S Heater Circuit History indicates the diagnostic state of the output driver for the heater control circuit. The scan tool displays OK, Open, Short, or Invalid.

HO2S 1 Heater Circuit Status

--

OK

The HO2S Heater Circuit Status indicates the diagnostic state of the output driver for the heater control circuit. The scan tool displays Fault, OK, or Invalid.

HO2S 1 Heater Command

--

On

The HO2S 1 Heater Command displays the commanded state of the HO2S heater. The scan tool displays ON or OFF.

HO2S 1 Ready

--

Yes

This parameter indicates whether the heated oxygen sensor 1 has reached the calibrated temperature to allow for closed loop fueling.

HO2S 2

--

0-1,000 mV

Represents the catalyst monitor exhaust O2S output voltage. If the catalyst is operating efficiently, the heated oxygen sensor (HO2S) 1 signal will be far more active than that produced by the HO2S 2 sensor. If the PCM detects a level of HO2S 2 activity that indicates the catalyst is no longer operating efficiently, DTC P0420 will be set.

HO2S 2 Heater

--

0.52 Amps

Varies

This parameter displays the current through the PCM when the HO2S heater is commanded ON by the PCM. HO2S Heater Sen. 2 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S 2 Heater Circuit History

--

OK

The HO2S Heater Circuit History indicates the diagnostic state of the output driver for the heater control circuit. The scan tool displays OK, Open, Short, or Invalid.

HO2S 2 Heater Circuit Status

--

OK

The HO2S Heater Circuit Status indicates the diagnostic state of the output driver for the heater control circuit. The scan tool displays Fault, OK, or Invalid.

HO2S 2 Heater Command

--

On

The HO2S 2 Heater Command displays the commanded state of the HO2S heater. The scan tool displays ON or OFF.

HO2S Heater Monitor Complete This Ignition

--

No

This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

HO2S Heater Monitor Enabled This Ignition

--

No

This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.

HO2S/O2S Monitor Complete This Ignition

--

No

This parameter displays the completion status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include: Yes or No.

HO2S/O2S Monitor Enabled This Ignition

--

Yes

This parameter displays the enable status during the current driving/monitoring cycle of the non-continuous legislated emission related monitor. The states include: Yes or No.

HOT Open Loop

--

Inactive

This parameter indicates the status of the fuel delivery system. The scan tool will display Active if the fuel system is running in open loop due to a temperature concern. The scan tool will display Inactive if the fuel system is operating normally.

IAT Sensor

--

Varies

The scan tool displays °C/F.

The PCM converts the resistance of the intake air temperature (IAT) sensor to degrees in the same manner as the engine coolant temperature (ECT) sensor. Intake air temp is used by the PCM to adjust fuel delivery and spark timing according to incoming air density.

The scan tool displays a range of -39 to +140°C (-38 to +284°F). The PCM converts the resistance of the intake air temperature sensor to degrees.

Ignition 1 Signal

--

12-14.5 Volts

This parameter displays the voltage measured at the ignition 1 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 1 position.

Ignition Mode

--

IC

Scan tool displays BYPASS or IC. Indicates the commanded state of the Bypass signal output from the PCM. When BYPASS is displayed, the ignition control module (ICM) is controlling the spark advance at a fixed 10 degrees before top dead center (BTDC), bypass mode. IC displayed indicates that the PCM has requested control of the spark advance, IC mode. The ICM determines the correct operating mode based on the level of voltage that the PCM applies to the ICM bypass circuit. The PCM provides 5 volts to the ICM bypass circuit when conditions are appropriate for PCM control of spark timing, IC mode. If the PCM does not apply 5 volts to the bypass circuit, or if the ICM does not receive the voltage , the module will control spark timing.

With ignition On, engine Off and during cranking

Bypass

Ignition Off Time

--

Varies

The Scan tool displays time in minutes.

This parameter is used by the PCM to identify the amount of time that has passed. This parameter is used for various components and systems including throttle actuator control (TAC) system and the EVAP system.

Ignition Voltage

--

13-14.5 Volts

This parameter displays the system voltage measured at the ignition feed.

IMS

--

Park

This parameter displays PARK, PARK/REVERSE, REVERSE, REVERSE/NEUTRAL, NEUTRAL, NEUTRAL/DRIVE 4, DRIVE 4, DRIVE 4/DRIVE 3, DRIVE 3, DRIVE 3/DRIVE 2, DRIVE 2, DRIVE 2/DRIVE 1, DRIVE 1 or INVALID. The IMS Range display represents a decoded status of the four inputs from the IMS. The combination of IMS inputs are used to determine which position the manual valve is in at any time.

In Reverse

Reverse

In Neutral

Neutral

In Drive

Drive 4

In 3rd

Drive 3

In 2nd

Drive 2

In 1st

Drive 1

IMS A/B/C/P

--

LOW HI HI LOW

This parameter displays the status of the four A/B/C/P inputs from the automatic transmission internal mode switch. I indicates an ignition voltage signal. LOW indicates a 0 voltage signal. The scan tool will display HI/LOW, HI/LOW, HI/LOW, HI/LOW.

In Reverse

LOW LOW HI HI

In Neutral

HI LOW HI LOW

In Drive

HI LOW LOW HI

In 3rd

LOW LOW LOW LOW

In 2nd

LOW HI LOW HI

In 1st

HI HI LOW LOW

Injector PWM

--

3.00-5.00 ms

Injector PWM indicates the commanded pulse width modulation of the fuel injectors. The scan tool displays milliseconds.

Knock Retard

--

Scan tool range 0.0-25.5 degrees. Indicates the amount of spark the PCM is removing from the IC spark advance in response to the signal from the knock sensors (KS). The traction control system Desired Torque signal from the electronic brake and traction control module (EBTCM) may cause knock retard to display a value more than 0.0 degrees if traction control is active.

Last Shift Time

--

0.00 Seconds

This parameter displays the actual time of the last upshift. This value is only accurate if the shift was adaptable.

Long Term FT

--

-10 to +10%

Long term FT is derived from the short term FT value and represents a long-term correction of fuel delivery. A value of 0 percent indicates that fuel delivery requires no compensation to maintain the PCM commanded air/fuel ratio. A negative value significantly below 0 percent indicates that the fuel system is rich and fuel delivery is being reduced, decreased injector pulse width. A positive value significantly more than 0 percent indicates that a lean condition exists and the PCM is compensating by adding fuel, increased injector pulse width. Because long term fuel trim tends to follow short term FT, a value in the negative range due to canister purge at idle should not be considered unusual. The PCM’s maximum authority to control Long term FT allows a range between -23 and +16 percent. Fuel trim values at or near maximum authority may indicate an excessively rich or lean system.

Loop Status

--

Closed

Closed loop indicates that the PCM is controlling fuel delivery according to oxygen sensor voltage. In open loop, the PCM ignores the oxygen sensor voltage and bases the amount of fuel to be delivered on throttle position (TP) sensor, ECT, and MAF sensor inputs only.

Low Engine Oil Level Indicator Command

--

Off

The scan tool displays ON or OFF. This is the state of the low engine oil level indicator as monitored by the PCM.

Low EOP Indicator Command

--

Off

The scan tool displays ON or OFF. This is the state of the low engine oil pressure indicator as monitored by the PCM.

MAF Sensor

--

3-6 g/s (varies with altitude)

The scan tool displays g/s

The scan tool displays a range of 0.0-655 g/s. The mass air flow (MAF) is the MAF input frequency converted to grams of air per second. This indicates the amount of air entering the engine.

MAF Sensor

--

1,200-1,300 Hz (varies with altitude)

The scan tool displays a range of 0-31,999 Hz. The MAF sensor is a hot wire type air flow sensor. The PCM converts current draw needed by the MAF to keep the hot wires at a constant into a frequency signal. The scan tool displays this frequency in a hertz signal.

MAP Sensor

--

20-48 kPa (varies with altitude)

The scan tool displays kPa

The MAP sensor measures the change in the intake manifold pressure which results from engine load and speed changes. As the intake manifold pressure increases, the air density in the intake also increases and additional fuel is required.

The scan tool displays a range of 10-105 kPa. The MAP sensor measures the absolute pressure in the intake manifold.

MAP Sensor

--

0.4-2.0 V (varies with altitude)

The scan tool displays Volts

The MAP sensor measures the change in the intake manifold pressure which results from engine load and speed changes. As the intake manifold pressure increases, the air density in the intake also increases and additional fuel is required.

The scan tool displays a range of 0-5 volts. The MAP sensor measures the absolute pressure in the intake manifold.

MIL Circuit History

--

OK

MIL Circuit History indicates the diagnostic state of the output driver for the MIL circuit. The scan tool displays OK, Open, Short or Invalid.

MIL Circuit Status

--

OK

This parameter displays the status of the output driver for the malfunction indicator lamp control circuit. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

MIL Command

--

Off

This parameter displays the commanded state of the MIL control circuit. The malfunction indicator lamp should be on when the scan tool indicates the MIL Command is On. The malfunction indicator lamp should be off when the scan tool indicates the MIL Command is Off. The control module will command the MIL On when the ignition is ON with the engine OFF in order to perform a bulb check.

Misfire Current Cyl. 1-6

--

0 Counts

The scan tool displays 0-255 counts. The display shows the number of misfires that have been detected during the last 200 cylinder firing events. The counters may normally display some activity, but the activity should be nearly equal for all of the cylinders, and in low numbers.

Misfire History Cyl. 1-6

--

0 Counts

The scan tool range is 0-255 counts. This parameter indicates the total level of misfire that has been detected on each cylinder. The misfire history counters will not update or show any activity until a misfire or DTC P0300 has become active. The misfire history counter will update every 200 cylinder firing events.

Number Of DTC(s)

--

0

This parameter displays the quantity of active DTCs.

PC Sol. Actual Current

--

0.96 Amps

Varies

This parameter displays the actual current flow through the pressure control solenoid circuit, which is measured by the PCM. High current flow results in low line pressure. Low current flow results in high line pressure.

PC Sol. Duty Cycle

--

57%

Varies

This parameter displays the commanded state of the pressure control solenoid, expressed as a percentage of energized ON time. A reading of low percent indicates zero ON time, non-energized, or no current flow. A high percent at idle indicates maximum ON time, energized, or high current flow.

PC Sol. Ref. Current

--

0.96 Amps

Varies

This parameter displays the commanded current of the pressure control solenoid circuit. High current results in low line pressure. Low current results in high line pressure.

Power Enrichment

--

Inactive

Scan tool displays ACTIVE or INACTIVE. ACTIVE displayed indicates that the PCM has detected conditions appropriate to operate in Power Enrichment mode. The PCM will command Power Enrichment mode when a large increase in throttle position and load is detected. While in Power Enrichment, the PCM will increase the amount of fuel delivered by entering Open Loop and increasing the injector pulse width. This is done to prevent a possible sag or hesitation from occurring during acceleration.

Reduced Engine Power

--

Inactive

The scan tool displays Active or Inactive. The scan tool displays Active when the PCM receives a signal from the TAC module that a throttle actuator control system fault is occurring. The PCM limits the engine power.

RVS Disable 1-8 History

--

--

These parameters show the last 8 reasons the PCM disabled remote vehicle start (RVS). Reason 1 is the most current reason.

Short Term FT

--

0%

The Short Term FT values change rapidly in response to the HO2S signal voltages. These changes fine tune the engine fueling. The Long Term FT values change in response to the trends in the Short Term FT. The Long Term FT makes coarse adjustments to the fueling in order to re-center and restore control to the Short Term FT. The Short Term FT and the Long Term FT can be monitored with a scan tool. A positive fuel trim value indicates that the PCM is adding fuel in order to compensate for a lean condition. A negative fuel trim value indicates that the PCM is reducing the amount of fuel in order to compensate for a rich condition.

Spark

--

18-24 Degrees

The scan tool displays a range of -64 to +64°. The scan tool displays the amount of degrees the PCM commands. The PCM computes the desired spark advance using the following: (1) ECT, (2) engine speed (RPM), (3) load, (4) vehicle speed. The PCM adjusts the timing.

A negative (-) value indicates degrees before top dead center (BTDC) or spark advance; a positive value indicates degrees after top dead center (ATDC) or spark retard.

Start-up ECT

--

Varies

Indicates the engine coolant temperature at engine start up.

The scan tool displays a range of -39 to +140°C (-38 to +284°F). The scan tool displays the engine ECT at the time the engine was started. The PCM uses start-up ECT for certain DTCs.

Indicates the engine coolant temperature at the time that the vehicle was started. Used to determine if the last startup was a cold start.

Start-up IAT

--

Varies

Indicates the IAT at the time that the vehicle was started. Used to determine if the last startup was a cold start.

The scan tool range is -39 to +140°C (-38 to +284°F). This parameter indicates the ambient air temperature at start-up.

Starter Relay Circuit History

--

OK

Starter Relay Circuit History indicates the diagnostic state of the output driver for the starter relay control circuit. The scan tool displays OK, Open, Short, or Invalid.

Starter Relay Circuit Status

--

OK

Starter Relay Circuit Status indicates the diagnostic state of the output driver for the starter relay control circuit. The scan tool displays Fault, OK or Invalid.

Starter Relay Command

--

Off

The scan tool displays ON or OFF. This displays the commanded state of the starter relay by the PCM.

Steady State TAP 1GR

--

Varies

This parameter displays a pressure modification which is added to the line pressure in FIRST gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 2GR

--

Varies

This parameter displays a pressure modification which is added to the line pressure in SECOND gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 2GR/TC

--

Varies

This parameter displays a pressure modification which is added to the line pressure in SECOND gear with TCC applied. The larger the value, the greater the increase to line pressure.

Steady State TAP 3GR

--

Varies

This parameter displays a pressure modification which is added to the line pressure in THIRD gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 3GR/TC

--

Varies

This parameter displays a pressure modification which is added to the line pressure in THIRD gear with TCC applied. The larger the value, the greater the increase to line pressure.

Steady State TAP 4GR

--

Varies

This parameter displays a pressure modification which is added to the line pressure in FOURTH gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 4GR/TC

--

Varies

This parameter displays a pressure modification which is added to the line pressure in FOURTH gear with TCC applied. The larger the value, the greater the increase to line pressure.

Steady State TAP Reverse

--

Varies

This parameter displays a pressure modification which is added to the line pressure in REVERSE gear. The larger the value, the greater the increase to line pressure.

Stoplamp Pedal Switch Signal

--

1.0 Volt

The Stop Lamp Signal displays the active position of the Stop Lamp Switch. The scan tool displays voltage.

Brake pedal depressed

10.5 Volts

TAC Vehicle Speed Signal

--

OK

This parameter indicates the status of the communication between the TAC module and the control module. The scan tool will display OK if the circuits are operating normally. The scan tool will display Fault if there is an interruption in the vehicle speed signal.

TAC/PCM Communication Signal

--

OK

This parameter indicates the status of the communication between the TAC module and the control module. The scan tool will display OK if the circuits are operating normally. The scan tool will display Fault if there is an interruption in the communication.

TCC Brake Switch

--

Closed

This parameter displays the position of the TCC brake switch.

Brake pedal depressed

Open

TCC Duty Cycle

--

0%

This parameter displays the commanded percentage of ON time for the TCC PWM solenoid. A high percentage represents an ON, energized, commanded state. 0 percent represents an OFF, non-energized, commanded state.

TCC Duty Cycle Ckt Status

--

OK

This parameter displays the solenoid driver feedback voltage signal and displays the circuit status on the scan tool. If the voltage is low when the solenoid is commanded OFF, the scan tool will display Open/Short to GND. If the voltage is high when the solenoid is commanded ON, the scan tool will display Short to Volts. If no circuit fault is present, the scan tool will display OK. Until the circuit has been evaluated, the scan tool will display Indeterminate.

TCC Release Pressure

--

Yes

This parameter displays the status of the normally closed TCC release switch and displays YES or NO. When TCC release fluid pressure is present, the switch is open, indicating that the TCC is released. When the fluid pressure is not present, the switch is closed, indicating that the TCC is applied.

TCC Slip Speed

--

5-15 RPM

This parameter displays the difference between transmission output speed and engine speed. A negative value indicates the engine speed is less than the output speed, deceleration. A positive value indicates the engine speed is greater than the output speed, acceleration. A value of zero indicates the engine speed is equal to the output speed, TCC applied.

TFT Sensor

--

95°C (203°F)

Varies

This parameter indicates the transmission fluid temperature measured by a sensor. In automatic transmission applications, this is based upon the transmission fluid temperature sensor input to the PCM.

TFT Sensor

--

2.43 Volts

Varies

This parameter displays the voltage drop across the transmission fluid temperature (TFT) sensor circuit. 5 volts is applied to the TFT sensor circuit. The sensor is a thermistor which changes internal resistance based on temperature. When the sensor is cold, the internal resistance is high, resulting in a high signal voltage. As the sensor warms, the internal resistance decreases, and the signal voltage will also decrease. A low signal voltage indicates a warm TFT, and a high signal voltage indicates a cold TFT.

Total Misfire

--

0 Counts

The scan tool range is 0-255 counts. This parameter indicates the total level of misfire that has been detected on each cylinder. The misfire history counters will not update or show any activity until a misfire or DTC P0300 has become active. The misfire history counter will update every 200 cylinder firing events.

TP Desired Angle

--

3%

This parameter indicates the TP angle commanded by the control module. The scan tool will display a low value at idle, and a high value at wide open throttle (WOT).

With ignition On, engine Off, accelerator pedal not actuated

19%

With ignition On, engine Off, accelerator pedal fully actuated

100%

TP Indicated Angle

--

3%

This parameter displays the angle of the throttle position (TP) in percent. This information is calculated by the control module using the signals from the throttle position sensors. The scan tool will display a low percentage when the throttle plates are closed. The scan tool will display a high percentage when the throttle plates are fully open.

With ignition On, engine Off, accelerator pedal not actuated

19%

With ignition On, engine Off, accelerator pedal fully actuated

100%

TP Sensor 1

--

0.71 Volt

This parameter displays the voltage signal sent to the control module from the sensor used to monitor the position of the throttle plates. This parameter is for sensor 1 of the throttle position (TP) sensor assembly. The scan tool will display a low voltage when the throttle plates are at rest. The scan tool will display a high voltage when the throttle plates are fully open.

With ignition On, engine Off, accelerator pedal not actuated

1.22 Volts

With ignition On, engine Off, accelerator pedal fully actuated

4.02 Volts

TP Sensor 1 Circuit Status

--

OK

This parameter indicates the diagnostic test state of the throttle position (TP) sensor 1 circuit. The scan tool displays OK or Fault.

TP Sensor 1 Indicated Position

--

3%

This parameter displays the angle of the TP sensor 1 in percent. This information is calculated by the control module using the signal from the throttle position sensor 1. The scan tool will display a low percentage when the throttle plates are closed. The scan tool will display a high percentage when the throttle plates are fully open.

With ignition On, engine Off, accelerator pedal not actuated

18%

With ignition On, engine Off, accelerator pedal fully actuated

100%

TP Sensor 2

--

0.73 Volt

This parameter displays the voltage signal sent to the control module from the sensor used to monitor the position of the throttle plates. This parameter is for sensor 2 of the throttle position (TP) sensor assembly. The scan tool will display a low voltage when the throttle plates are at rest. The scan tool will display a high voltage when the throttle plates are fully open.

With ignition On, engine Off, accelerator pedal not actuated

1.24 Volts

With ignition On, engine Off, accelerator pedal fully actuated

4.02 Volts

TP Sensor 2 Circuit Status

--

OK

This parameter indicates the diagnostic test state of the throttle position (TP) sensor 2 circuit. The scan tool displays OK or Fault.

TP Sensor 2 Indicated Position

--

3%

This parameter displays the angle of the TP sensor 2 in percent. This information is calculated by the control module using the signal from the throttle position sensor 2. The scan tool will display a low percentage when the throttle plates are closed. The scan tool will display a high percentage when the throttle plates are fully open.

With ignition On, engine Off, accelerator pedal not actuated

18%

With ignition On, engine Off, accelerator pedal fully actuated

100%

TP Sensors 1 and 2

--

Agree

This parameter displays the results of a control module test that compares the signals from the TP sensors 1 and 2. The scan tool will display Agree when the signal from TP sensor 1 corresponds with the signal from TP sensor 2. The scan tool will display Disagree when the signal from TP sensor 1 conflicts with the signal from TP sensor 2.

Traction Control Signal

--

Inactive

This parameter displays Active or Inactive. When the PCM receives a request for torque reduction from the electronic brake traction control module (EBTCM), Active is displayed.

Traction Control Status

--

Inactive

Scan tool displays ACTIVE or INACTIVE. ACTIVE displayed indicates that the traction control system is taking action to reduce drive wheel slippage.

Trans. Fluid Temp

--

78°C (172°F)

Varies

This parameter displays the input signal of the transmission fluid temperature sensor. Transmission fluid temperature is high, 151°C (304°F), when signal voltage is low, 0 volt. Transmission fluid temperature is low, -40°C (-40°F), when signal voltage is high, 5 volt.

Transmission Hot Mode

--

Off

This parameter displays the automatic transmission fluid temperature (TFT) and displays On or Off. Off indicates that the TFT has not exceeded 130°C (266°F). On indicates that the TFT has exceeded 130°C (266°F) and has not cooled to 120°C (248°F) for greater that 5 seconds. These numbers are approximate and differ with transmissions.

Transmission ISS

--

Same as engine speed

This parameter displays the rotational speed of the transmission input shaft. The scan tool displays input shaft speed as revolutions per minute (RPM).

Transmission OSS

--

0 RPM

This parameter displays the rotational speed of the transmission output shaft. The scan tool displays output shaft speed as revolutions per minute (RPM).

TWC Temperature Calculated

--

534°C (993°F)

Varies

Calculated catalytic converter temperature.

Vehicle Security Status

--

--

The scan tool displays Fuel Enabled/Fuel Disabled/Fuel Off for Ign/Learn Timer On/Fail Enable/Learn Enabled. The scan tool displays the current state of the vehicle theft deterrent (VTD) state.

Vehicle Speed

--

0 km/h (0 mph)

This parameter displays the speed at which the vehicle is traveling. The scan tool displays vehicle speed as kilometers per hour (km/h), miles per hour (mph). The vehicle speed is calculated based on the input signal from the vehicle speed sensor.

Vehicle Speed Circuit History

--

OK

This parameter indicates the diagnostic test state of the vehicle speed sensor circuit. The scan tool displays OK, Open, Short or Invalid.

Vehicle Speed Circuit Status

--

OK

This parameter indicates the diagnostic test state of the throttle position (TP) sensor 1 circuit. The scan tool displays OK, Fault, or Invalid.

Vehicle Speed Sensor

--

0 km/h/mph

The scan tool range is 0-200 km/h (0-125 mph). This parameter displays the vehicle speed. The PCM receives reference pulses from the vehicle speed sensor (VSS) and converts them into km/h and mph for display.

Warm-ups Since DTC Cleared

--

Varies

The scan tool displays a range of 0-255. This parameter counts the number of warm up cycles since a DTC was cleared from memory. The scan tool displays counts.

Warm-ups w/o Emission Faults

--

Varies

The scan tool displays a range of 0-255. This parameter counts the number of warm up cycles without an emission fault present. The counter increments to 255 and rolls back to 0 unless a fault occurs. If a fault occurs, the counter reverts back to 0 until the fault is corrected. Clearing the information with a scan tool or a loss of power to the PCM also resets the counter to 0. The scan tool displays counts. This display indicates the number of warm-up cycles without a emission failure.

Warm-ups w/o Non-Emission Faults

--

Varies

The scan tool displays a range of 0-255. This parameter counts the number of warm up cycles without a non-emission fault present. The counter increments to 255 and rolls back to 0 unless a fault occurs. If a fault occurs, the counter reverts back to 0 until the fault is corrected. Clearing information with a scan tool or a loss of power to the PCM also resets the counter to 0.

Powertrain Control Module Scan Tool Output Controls

Output Control

Description

1-2 Solenoid

    • The powertrain control module (PCM) commands the 1-2 shift solenoid valve ON and OFF. The scan tool 1-2 Sol. parameter should match the commanded state. The scan tool Commanded Gear parameter should correspond with the shift solenoid combination. Refer to the Shift Solenoid Valve State and Gear Ratio table.
    • When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the PCM.
    • When the engine is running, the following control limits apply:
       - Only sequential gear changes are allowed. For example, FIRST to THIRD is not allowed. If a non-sequential gear change is attempted, the message Non-Sequential Gear Changes Not Allowed. Gear Changes Must Be In Order appears on the scan tool display.
       - The vehicle speed must be below a calibrated value. If the vehicle speed is too high, the message Vehicle Speed Too High Appears on the scan tool display.
       - The gear requested may not be greater than the current selected transmission range (PRNDL). For example, THIRD gear is not allowed if the transmission range is D2. If the gear requested is greater than the current selected transmission range, the message Eng. Running And Gear Request Is Greater Than The Current TR appears on the scan tool display.
       - The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the PCM.

2-3 Solenoid

    • The PCM commands the 2-3 shift solenoid valve ON and OFF. The scan tool 2-3 Sol. parameter should match the commanded state. The scan tool Commanded Gear parameter should correspond with the shift solenoid combination. Refer to the Shift Solenoid Valve State and Gear Ratio table.
    • When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid will remain ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the PCM.
    • When the engine is running, the following control limits apply:
       - Only sequential gear changes are allowed. For example, FIRST to THIRD is not allowed. If a non-sequential gear change is attempted, the message Non-Sequential Gear Changes Not Allowed. Gear Changes Must Be In Order appears on the scan tool display.
       - The vehicle speed must be below a calibrated value. If the vehicle speed is too high, the message Vehicle Speed Too High appears on the scan tool display.
       - The engine speed must be below a calibrated value. If the engine speed is too high, the message Engine Speed Too High appears on the scan tool display.
       - Downshifts are allowed only when the vehicle speed is below a calibrated value. If the vehicle speed is too high, the message Eng. Is On And Veh. Speed Too Hi for 3-2 or 2-1 Downshift appears on the scan tool display.
       - The gear requested may not be greater than the current selected transmission range (PRNDL). For example, THIRD gear is not allowed if the transmission range is D2. If the gear requested is greater than the current selected transmission range, the message Eng. Running And Gear Request Is Greater Than The Current TR appears on the scan tool display.
       - The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the PCM.

A/C Relay

The commanded states are ON or OFF. The command turns the A/C relay ON or OFF, which engages or disengages the A/C compressor clutch.

AIR Pump Relay

This output control is used to turn the AIR pump ON or OFF.

AIR Solenoid

Commands the AIR solenoid relay to open and close the AIR control/Shut-off valve.

APP Learn

Learns the minimum throttle opening. Follow the instructions on the scan tool.

Crankshaft Pos. Variation Learn

This output control is used to activate the crankshaft position variation learn (CASE) algorithm which calculates the reference pulse correction factors for the misfire diagnostic.

Cylinder Power Balance

Enables/disables a cylinder by turning OFF the fuel injector to the cylinder.

The fuel injector is normally enabled. The control module disables the fuel injector when the following conditions are met:

    • All the instructions on the scan tool have been completed.
    • The engine speed has stabilized.
    • The fuel injector has been selected.

When DISABLE is selected, the PCM turns the injector OFF for 30 seconds.

EGR Solenoid

Activates the exhaust gas recirculation (EGR) solenoid in 10 percent increments from 0 to 100 percent or a maximum of 30 seconds at 100 percent.

Engine Speed Control

Activates the throttle activation control (TAC) system to change engine RPM. The normal commanded state is None. To enable the RPM control, all instruction on the scan tool must be completed. The system will increase or decrease the RPM within a range of 400-2,200 RPM. The set step value changes the RPM by increments of 25 RPM, 100 RPM, and 500 RPM. The system remains in the commanded state until cancelled by the scan tool.

EVAP Purge/Seal

Simultaneously activates the purge solenoid in 10 percent increments from 0 to 100 percent and the vent solenoid. The device control will be aborted and inhibited if the FTP sensor exceeds 19 mm Hg (10 in H2O).

EVAP Purge Solenoid

Activates the purge solenoid in 10 percent increments from 0 to 100 percent. The device control will be aborted and inhibited if the fuel tank pressure (FTP) sensor exceeds 19 mm Hg (10 in H2O).

EVAP Service Bay Test

Activates the on-board EVAP diagnostic test.

EVAP Vent Solenoid

Activates the vent solenoid. The device control will be aborted and inhibited if the FTP sensor exceeds 19 mm Hg (10 in H2O).

Fans Low Speed

The scan tool displays a Commanded State of None, Off or On. This allows you to communicate with the PCM and activate or deactivate the cooling fan 1 relay, manually turning the low speed fans On and Off.

Fan High Speed

The scan tool displays a Commanded State of None, Off or On. This allows you to communicate with the PCM to activate or deactivate the cooling fan 1 relay, manually turning the low speed fans On. After a 3-second delay the PCM will activate the cooling fan S/P relay and the cooling fan 2 relay. This turns the high speed fans On and Off.

Fuel Injector Balance

Enables the fuel injector in order to verify proper fuel injector flow. The PCM will pulse the selected injector when the following conditions are met:

    • All instruction on the scan tool completed.
    • Fuel injector selected
    • Key ON, engine OFF

The selected fuel injector can only be flowed/pulsed once per ignition cycle.

Fuel Pump

Activates the fuel pump relay for 2 seconds. Also turns fuel pump ON and OFF while engine is running.

Fuel Trim Enable

Disables the PCM ability to learn new fuel trim parameters. The commanded states are NONE, ENABLED, DISABLED. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the scan tool.

Fuel Trim Reset

Activates the reset of fuel trim data in all fuel trim cells.

GEN L-Terminal

The commanded states are ON and OFF. Selecting OFF commands the ECM to turn OFF the generator and stop generating an output voltage.

Heated Oxygen Sensors

Activates the heated oxygen sensor (HO2S) heater. The commanded states include NONE, On, and Off. The normal commanded state is NONE. The system remains in the commanded state until cancelled by the tool.

Loop Status

Controls the system loop status. The commanded states include NONE, OPEN, or CLOSED. The normal commanded state is NONE. When commanded OPEN or CLOSED, the system remains in the commanded state until cancelled by the scan tool.

Malfunction Indicator Lamp

Activates the malfunction indicator lamp (MIL). The MIL will remain illuminated until cancelled by the scan tool.

Misfire Graphic

Graphs the accumulated misfires occurring in each cylinder. The scan tool allows for a reset of the misfire graph.

Oil Life Reset

The engine oil remaining life is determined from an algorithm based upon the effective engine revolutions and the distance driven since the last oil change. This output control may be used to reset the engine oil remaining life.

PC Solenoid

    • The PCM commands the amperage, current, to the pressure control solenoid valve in order to control transmission line pressure. As the amperage increases, the line pressure decreases. As the amperage decreases, the line pressure increases. The amperage range is 0.00-1.10 and may be commanded in one-tenth amp increments.
    • When the ignition is ON, and the engine is OFF, the reference, commanded, amperage may be controlled within calibrated limits. The scan tool parameter PC Sol. Ref. Current changes, but the parameter PC Sol. Actual Current does not change. The reference current remains until commanded otherwise.
    • When the engine is running, the following control limits apply:
       - When the transmission range is PARK or NEUTRAL, the reference, commanded, amperage may be controlled within calibrated limits. The engine speed must be less than 1,500 RPM. If the engine speed is greater than 1,500 RPM, the message TR in Park/Neutral And Engine Speed Over 1,500 RPM appears on the scan tool display. Both the scan tool parameters PC Sol. Ref. Current and PC Sol. Actual Current change. Both current readings remain until commanded otherwise.
       - When the transmission range is not in PARK or NEUTRAL, the reference amperage can only be controlled less than the current determined by the PCM. The PCM does not allow a value to be selected that may cause damage to the transmission. If the requested amperage is more than allowed by the PCM, the message Requested Current For The PC Solenoid Is Too High appears on the scan tool display.
       - Transmission range DTCs must not be active. If a transmission range DTC is active, the message Engine Running With Transmission DTC Present appears on the scan tool display.

Reset Transmission Adapts

    • The PCM clears, or resets, the TAP cells to the original base value.
    • There are no limits to using this output control. It may be performed with the engine running or when the ignition is ON, and the engine is OFF.

Shift Transmission

    • The PCM commands upshifts and downshifts. The scan tool Commanded Gear parameter should correspond with the shift solenoid combination. Refer to the Shift Solenoid Valve State and Gear Ratio table.
    • When the ignition is ON, and the engine is OFF, there are no limits to this control. The scan tool shift solenoid states change to match the Current Gear selected.
    • When the engine is running, the following control limits apply:
       - The PCM does not allow a shift if it causes the engine RPM to exceed a calibrated limit. If a gear is requested and the engine speed is too high, the message Engine Speed Too High appears on the scan tool display.
       - The PCM does not allow a 3-2 or 2-1 downshift if the vehicle speed exceeds a calibrated limit. If either downshift is requested and the vehicle speed is too high, the message Eng. Is On And Veh. Speed Too Hi for 3-2 or 2-1 Downshift appears on the scan tool display.
       - The PCM does not allow a 4-3 downshift if the vehicle speed exceeds a calibrated limit. If a 4-3 downshift is requested and the vehicle speed is too high, the message Vehicle Speed Too High appears on the scan tool display.
       - The PCM does not allow an upshift if the vehicle speed exceeds a calibrated limit. If an upshift is requested and the vehicle speed is too high, the message Vehicle Speed Too High appears on the scan tool display.
       - The PCM does not allow an upshift that is greater than the current selected transmission range (PRNDL). For example, THIRD gear is not allowed if the transmission range is D2. If an upshift is requested that is greater than the current selected transmission range, the message Eng. Running And Gear Request Is Greater Than The Current TR appears on the scan tool display.

TCC Control Solenoid

    • The PCM commands the duty cycle of the TCC PWM solenoid valve. The duty cycle is represented by a percentage of ON energized time. Approximately 90-100 percent duty cycle represents an ON energized commanded state. Zero percent represents an OFF non-energized commanded state. The scan tool TCC Duty Cycle parameter should match the commanded state.
    • When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid remains ON, 90-100 percent duty cycle until commanded OFF, zero percent duty cycle, and vice versa. When the output control is exited, the solenoid duty cycle is determined by the PCM.
    • When the engine is running, the following control limits apply:
       - If the transmission range is PARK, and the transmission is in hot mode, the TCC PWM solenoid valve may not be commanded OFF. If the solenoid is requested OFF, the message TCC Off Command Disabled In Hot Mode appears on the scan tool display.
       - The TCC PWM solenoid valve may not be commanded OFF for more than a calibrated amount of time. If the solenoid is commanded OFF, for a certain amount of time, the message TCC Off Time Has Been Exceeded appears on the scan tool display.

Throttle Position

Operates TAC motor in 10 percent increments to open or close the throttle blade. The test operates during key ON, engine OFF.