GM Service Manual Online
For 1990-2009 cars only

Object Number: 368338  Size: SF
Engine Controls Components
Engine Controls Schematics
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The manifold absolute pressure (MAP) sensor responds to changes in intake manifold pressure (vacuum). The MAP sensor signal voltage to the PCM varies from less than 2 volts at idle (high vacuum) to more than 4 volts with the key ON, engine not running or at wide-open throttle (low vacuum). The MAP sensor determines the manifold pressure changes while running the EGR flow test diagnostic, and updates the barometric pressure reading (BARO). The PCM monitors the MAP signals for voltages outside the normal range of the MAP sensor. If the PCM detects a MAP sensor signal voltage that is excessively low, DTC P0107 will set.

Conditions for Running the DTC

    • No TP sensor DTCs present.
    • Ignition voltage is more than 8 volts.
    • The engine is running.
    • Throttle angle is more than or equal to 10 percent, when engine speed is less than or equal to 900 RPM.

Conditions for Setting the DTC

The MAP sensor indicates less than 12 kPa.

Action Taken When the DTC Sets

    • The PCM will illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
    • The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

Conditions for Clearing the MIL/DTC

    • The PCM will turn OFF the malfunction indicator lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.
    • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
    • The DTC can be cleared by using a scan tool.

Diagnostic Aids

Inspect for the following:

Many situations may lead to an intermittent condition. Perform each inspection or test as directed.

Important: :  Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.

    • Loose terminal connection
       -  Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair.
       -  Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair.
    • Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair.
    •  Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair.

If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.

Test Description

The numbers below refer to the step numbers on the diagnostic table:

  1. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.

P0107- MAP Sensor Circuit Low Voltage

Step

Action

Values

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Important::  Refer to DTC P1635 5 Volt Reference 1 Circuit or DTC P1639 5 Volt Reference 2 Circuit first, if set.

  1. Turn ON the ignition, with the engine OFF.
  2. With the scan tool and the throttle closed, observe the MAP voltage parameter.

Does the MAP voltage measure less then the specified value?

0.1 volt

Go to Step 4

Go to Step 3

3

Operate the vehicle within Fail Record conditions.

Does the scan tool indicate DTC P0107 failed?

--

Go to Step 4

Go to Diagnostic Aids

4

  1. Disconnect the MAP sensor.
  2. Connect a 3 amp jumper between the 5 volt reference circuit and the MAP signal circuit.
  3. With a scan tool, observe the MAP voltage parameter.

Does the scan tool indicate voltage at near the specified value?

4.95V

Go to Step 9

Go to Step 5

5

  1. Disconnect the jumper wire.
  2. Connect a test lamp between battery positive voltage and the MAP sensor signal circuit.
  3. With a scan tool, observe the MAP voltage parameter.

Does the scan tool indicate voltage at or near the specified value?

4.95V

Go to Step 6

Go to Step 8

6

  1. Turn OFF the ignition.
  2. Test the 5 volt reference circuit of the MAP sensor for high resistance or an open.
  3. Repair as necessary. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 7

7

Inspect the 5 volt reference circuit of the MAP sensor for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 12

8

Test the signal circuit of the MAP sensor for an open, short to ground, or short to the sensor ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 10

9

Test the signal circuit and the 5 volt reference circuit of the MAP sensor for a poor connection at the MAP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 11

10

Test the signal circuit and the 5 volt reference circuit of the MAP sensor for a poor connection at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems

Did you find and correct the condition?

--

Go to Step 13

Go to Step 12

11

Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement .

Did you complete the replacement?

--

Go to Step 13

--

12

Important:: Perform the set up procedure for the PCM.

Replace the PCM.

Refer to Powertrain Control Module Replacement/Programming .

Did you complete the replacement?

--

Go to Step 13

--

13

  1. Use a scan to in order to clear the DTCs.
  2. Operate the vehicle within the Fail Record conditions.

Does the DTC reset?

--

Go to Step 2

System OK