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For 1990-2009 cars only

Scan Tool Output Controls

Scan Tool Output Control

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Description

Line PC Solenoid

Line PC Sol. Electrical

    • The TCM commands the amperage, current, to the line pressure control solenoid 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 0.20-1.10 and may be commanded in one-tenth amp increments. If an amperage below 0.20 amp is commanded, the message "Requested override current out of range" appears on the scan tool display.
    • The Line PC Sol. Electrical output control can be performed when the ignition is ON, and the engine is OFF. The reference, commanded, amperage may be controlled within calibrated limits. The scan tool parameter "Line PC Sol. Ref. Current" changes, but the parameter "Line PC Sol. Actual Current" does not change. The reference current remains until commanded otherwise. If output control is attemped while the engine is running, the message "Output control not allowed while engine is running" appears on the scan tool display.

Line PC Sol. Functional

    • The TCM commands the amperage, current, to the line pressure control solenoid 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.
    • The Line PC Sol. Functional output control can be performed 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. Both the scan tool parameters "Line PC Sol. Ref. Current" and "Line PC Sol. Acutal Current" change. Both current readings remain until commanded otherwise.
       - When the transmission range is not Park or Neutral, the message "Transmission NOT is Park or Neutral" 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.

TCC PC Solenoid

TCC PC Sol. Electrical

    • The TCM commands the duty cycle of the TCC pressure control solenoid. 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 PC Sol. Duty Cycle parameter should match the commanded state.
    • The TCC PC Sol. Electrical output control can be performed 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 TCM. If output control is attemped while the engine is running, the message "Output control not allowed while engine is running" appears on the scan tool display.

TCC PC Sol. Functional

    • The TCM commands the duty cycle of the TCC pressure control solenoid. 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 PC Sol. Duty Cycle parameter should match the commanded state.
    • The TCC PC Sol. Functional output control can be perfomed when the engine is running. The following control limits apply:
       - If the transmission range is 3rd, 4th, or 5th, and the transmission is in hot mode, the TCC control solenoid 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 control solenoid 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.
       - The TCC control solenoid may not be commanded ON if the vehicle speed is below a calibrated limit. If the solenoid is commanded ON below the calibrated limit the message "Vehicle speed too low" appears on the scan tool display.

Shift PC Sol. Electrical

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    • The TCM commands the amperage, current, to the shift pressure control solenoid 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 0.20-1.10 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 "Shift PC Sol. Ref. Current" changes, but the parameter "Shift PC Sol. Actual Current" does not change. The reference current remains until commanded otherwise.
    • When the engine is running, the following control limits apply:
       - If output control is attemted while the engine is running, the message "Output control not allowed while engine is running" 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 transmisssion DTC present" appears on the scan tool display.

Shift Solenoid

Shift Solenoid 1

    • The TCM commands the reverse, 1st shift solenoid valve (S1) ON and OFF. The scan tool Shift Solenoid 1 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 OFF until commanded ON, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
    • This output control is not allowed when the engine is running. If the engine is running, the output control will abort, and the message "Output Control not allowed while Engine is Running" appears on the scan tool.

Shift Solenoid 2

    • The TCM commands the 2-3, 3-4 shift solenoid valve (S2) ON and OFF. The scan tool Shift Solenoid 2 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 OFF until commanded ON, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
    • This output control is not allowed when the engine is running. If the engine is running, the output control will abort, and the message "Output Control not allowed while Engine is Running" appears on the scan tool.

Shift Solenoid 3

    • The TCM commands the 1-2, 2-3, reverse shift solenoid valve (S3) ON and OFF. The scan tool Shift Solenoid 3 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 OFF until commanded ON, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
    • This output control is not allowed when the engine is running. If the engine is running, the output control will abort, and the message "Output Control not allowed while Engine is Running" appears on the scan tool.

Shift Solenoid 4

    • The TCM commands the 3-4, 4-5 shift solenoid valve (S4) ON and OFF. The scan tool Shift Solenoid 4 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 OFF until commanded ON, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
    • This output control is not allowed when the engine is running. If the engine is running, the output control will abort, and the message "Output Control not allowed while Engine is Running" appears on the scan tool.

Shift Solenoid 5

    • The TCM commands the reverse shift solenoid valve (S5) ON and OFF. The scan tool Shift Solenoid 5 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 OFF until commanded ON, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
    • This output control is not allowed when the engine is running. If the engine is running, the output control will abort, and the message "Output Control not allowed while Engine is Running" appears on the scan tool.

Shift Trans.

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    • The TCM commands upshifts and downshifts. The scan tool Commanded Gear parameter should match the commanded state.
    • 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 Commanded Gear selected.
    • When the engine is running, the following control limits apply:
       - The TCM does not allow a shift if it will cause the engine RPM to exceed a calibrated limit. If a gear is requested and the engine speed is too high, the message "Engine speed to high" appears on the scan tool display.
       - The TCM 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 TCM 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 TCM 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.

Trans. Adaptives Reset

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    • The TCM clears, or resets, all TAP cells to zero.
    • There are no limits to using this control. It may be performed with the engine running or when the ignition is ON, and the engine is OFF.

Trans. Oil Life Reset

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    • The TCM resets the amount of transmission oil life remaining to a value selected.
    • There are no limits to using this control. It may be performed with the engine running or when the ignition is ON, and the engine is OFF.