GM Service Manual Online
For 1990-2009 cars only

Object Number: 237054  Size: SF
Engine Controls Component Views
Engine Data Sensors-A/C Refrig Press, TP, MAP, ECT, IAT
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 below 2 volts at idle (high vacuum) to above 4  volts with the key ON, engine not running or at wide-open throttle (low vacuum). The MAP sensor is used to determine manifold pressure changes while the EGR flow test diagnostic is being run, refer to DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient , to determine engine vacuum level for some other diagnostics and to determine barometric pressure (BARO). 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 set.

Conditions for Running the DTC

    • No TP sensor DTCs present.
    • System voltage is more than 9 volts.
    • The engine is running.
    • Idle speed is steady.
    • Throttle angle above 0 percent, if engine speed is less than 1000 RPM.
    • Throttle angle above 10 percent, if engine speed is more 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 a scan tool.

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 Table may isolate the cause of the malfunction.

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.

DTC P0107 - MAP Sensor Circuit Low Voltage

Step

Action

Value(s)

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

  1. Turn ON the ignition switch.
  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 4

3

  1. Turn ON the ignition switch.
  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?

4.6 V

Go to Step 10

Go to Step 5

5

  1. Connect a J 35616-200 test lamp 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 OFF the ignition switch.
  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 Wiring Repairs in Wiring Systems.

Was a problem found?

--

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 Wiring Repairs in Wiring Systems.

Was a problem found?

--

Go to Step 12

Go to Step 11

8

  1. Turn OFF the ignition switch.
  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 Wiring Repairs in Wiring Systems.

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 Wiring Repairs in Wiring Systems.

Was a problem found?

--

Go to Step 12

Go to Step 11

10

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

Did you complete the repair?

--

Go to Step 12

--

11

Important: The replacement PCM must be programmed.

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Did you complete the repair?

--

Go to Step 1

--

12

  1. Turn ON the ignition switch.
  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