GM Service Manual Online
For 1990-2009 cars only

Object Number: 154580  Size: MF
Engine Controls Components
Engine Data Sensors-A/C Refrig Press, TP, MAP, ECT, IAT
OBD II Symbol Description Notice

Circuit Description

The Manifold Absolute Pressure (MAP) sensor responds to changes in the intake manifold pressure. The PCM supplies a 5 volt reference and a ground for the MAP sensor. The MAP sensor provides a signal to the PCM relative to pressure changes in the manifold. The MAP sensor signal voltage to the PCM varies from below 2 volts at idle (low manifold absolute pressure - high vacuum) to above 4 volts with the key ON, engine not running or at wide open throttle (high manifold absolute pressure - low vacuum). The PCM monitors the MAP signals for voltages outside the normal range of the MAP sensor. If the PCM detects a MAP signal voltage that is excessively low, DTC P0107 will be set.

Conditions for Running the DTC

    • No TP sensor DTCs present.
    • The engine is running.
    • Idle speed is steady.
    • Throttle angle above 0%, if engine speed is less than 1000 RPM.
    • Throttle angle above 10%, if engine speed is greater than 1000 RPM.

Conditions for Setting the DTC

    • The MAP sensor signal voltage is less than 0.1 volt.
    • Above conditions present for longer than 200 3X reference periods (67 crankshaft revolutions).

Action Taken When the DTC Sets

    • The PCM will illuminate the 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 and Fail Records data.

Conditions for Clearing the MIL/DTC

    • The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been 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 the scan tool Clear Info function or by disconnecting the PCM battery feed.

Diagnostic Aids

Check for the following conditions:

    • Poor connection at the PCM. Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
    • Damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the MAP display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the display will indicate the location of the malfunction.

If DTC P0107 cannot be duplicated, the information included in the Fail Records data can be useful in determining since the DTC was last set. If it is determined that the DTC occurs intermittently, performing the DTC P1107 Diagnostic Chart may isolate the cause of the malfunction.

Test Description

Number(s) below refer to the step number(s) 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.

DTC P0107 - MAP Sensor Circuit Low Voltage

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to the Powertrain On Board Diagnostic (OBD) System Check

2

  1. Turn the ignition switch to the ON position.
  2. Observe the MAP value displayed on the scan tool.

Is MAP value near the specified value?

0V

Go to Step 5

Go to Step 3

3

  1. Turn the ignition switch to the ON position.
  2. Review and record scan tool Fail Records data.
  3. Operate the vehicle within Fail Records conditions.
  4. Using a scan tool, monitor Specific DTC info for DTC P0107.

Does the scan tool indicate DTC P0107 failed?

--

Go to Step 4

Go to Diagnostic Aids

4

  1. Disconnect the MAP sensor electrical connector.
  2. Jumper the 5 volt reference A circuit and the MAP signal together at the MAP sensor harness connector.
  3. Observe the MAP value displayed on the scan tool.

Is the MAP value greater than the specified value?

4.6V

Go to Step 10

Go to Step 5

5

  1. Connect a test light between B+ and the MAP sensor signal circuit at the MAP sensor harness connector.
  2. Observe the MAP value displayed on the scan tool.

Is the MAP value near the specified value?

4.6V

Go to Step 6

Go to Step 8

6

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the PCM.
  3. Check the 5 volt reference A circuit for an open or short to ground.
  4. If the 5 volt reference A circuit is open or shorted to ground, repair it as necessary. Refer to Repair Procedures in Wiring Repairs .

--

Go to Step 12

Go to Step 7

7

  1. Check the 5 volt reference A circuit for a poor connection at the PCM.
  2. If a problem is found, repair as necessary. Refer to Repair Procedures in Wiring Repairs .

Was a problem found?

--

Go to Step 12

Go to Step 11

8

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the PCM.
  3. Check the MAP signal circuit for an open, short to ground, or short to the sensor ground circuit.
  4. If the MAP sensor signal circuit is open or shorted to ground, repair it as necessary. Refer to Repair Procedures in Wiring Repairs .

Was a problem found?

--

Go to Step 12

Go to Step 9

9

  1. Check the MAP sensor signal circuit for a poor connection at the PCM.
  2. If a problem is found, repair as necessary. Refer to Repair Procedures in Wiring Repairs .

Was a problem found?

--

Go to Step 12

Go to Step 11

10

  1. Check for poor terminal connections at the MAP sensor.
  2. If a problem is found, repair as necessary. Refer to Repair Procedures in Wiring Repairs .
  3. If the terminal connections are OK, replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement .

Is action complete?

--

Go to Step 12

--

11

Replace the PCM.

Important:: The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming .

Is action complete?

--

Go to Step 12

--

12

  1. Turn the ignition switch to the ON position.
  2. Review and record scan tool Fail Records data.
  3. Clear DTCs.
  4. Operate the vehicle within Fail Records conditions.
  5. Using a scan tool, monitor Specific DTC info for DTC P0107.

Does the scan tool indicate DTC P0107 failed?

--

Go to Step 4

System OK