GM Service Manual Online
For 1990-2009 cars only

Refer to Engine Controls Schematics

A/C Pressure Switch, TPS, MAP, ECT and IAT


Object Number: 590134  Size: FS
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Engine Controls Component Views
Powertrain Control Module Description
Heated O2 Sensors
Fuel Injectors
OBD II Symbol Description Notice
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Circuit Description

The manifold absolute pressure (MAP) sensor is mounted to the top of the intake manifold. The MAP sensor measures pressure changes within the intake manifold which are an indication of engine load. The MAP sensor has a 5.0 volt reference, a ground, and a signal circuit.

The MAP sensor contains a diaphragm which changes resistance based on pressure. When manifold pressure is low, or the vacuum is high, sensor output voltage is low. When manifold pressure is high, or the vacuum is low, sensor output voltage is high. MAP sensor voltage, depending on altitude, can range from below 2 volts at idle to above 4 volts at wide open throttle (WOT) or with the engine not running.

The MAP sensor signal is also used at initial key-up to determine barometric pressure (BARO).

Conditions for Running the DTC

    • No throttle position (TP) sensor DTCs present.
    • The engine is running.
    • The idle speed is steady.
    • The throttle angle above 0 percent, if engine speed is less than 1000 RPM.
    • The throttle angle above 10 percent, if engine speed is more than 1000 RPM.

Conditions for Setting the DTC

    • The manifold absolute pressure (MAP) sensor signal voltage is less than 0.1 volt.
    • The above conditions present for approximately 10 seconds.

Action Taken When the DTC Sets

    • The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

    • The PCM turns the MIL OFF after 3 consecutive drive trips during which the diagnostic runs and passes.
    • A last test failed, or the current DTC, clears when the diagnostic runs and passes.
    • A History DTC clears after 40 consecutive warm-up cycles, if no other emission related diagnostic failures are reported.
    • Use a scan tool in order to clear the MIL diagnostic trouble code.
    • Interrupting the PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Powertrain Control Module Description , Clearing Diagnostic Trouble Codes.

Diagnostic Aids

Notice: Use the connector test adapter kit J 35616-A for any test that requires probing the following items:

   • The PCM harness connectors
   • The electrical center fuse/relay cavities
   • The component terminals
   • The component harness connector
Using this kit will prevent damage caused by the improper probing of connector terminals.

If DTC P0107 cannot be duplicated, the information included in the Fail Records data can be useful in determining the vehicle mileage since the DTC was last set.

If the problem is intermittent, refer to Intermittent Conditions .

Test Description

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.

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

Observe the MAP value displayed on the scan tool.

Is MAP value near the specified value?

0 V

Go to Step 4

Go to Step 3

3

  1. Turn the key to the Off position, wait 15 seconds then turn the key to the On position.
  2. Review and record the Failure Records data.
  3. Operate the vehicle within Failure Records conditions.
  4. Using a scan tool, monitor Specific DTC info for DTC P0107.

Does the scan tool indicate DTC P0107 failed this ign?

--

Go to Step 4

Go to Diagnostic Aids.

4

  1. Turn off the engine, then turn the key to the On position.
  2. Disconnect the MAP sensor electrical connector.
  3. Jumper the 5 volt reference circuit and the MAP signal together at the MAP sensor harness connector.
  4. Observe the MAP value displayed on the scan tool.

Is the MAP value more than the specified value?

4.6 V

Go to Step 10

Go to Step 5

5

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

Is the MAP value near the specified value?

4.6 V

Go to Step 6

Go to Step 8

6

  1. Turn the key to Off.
  2. Disconnect the PCM.
  3. Check the 5 volt reference circuit for an open or a short to ground.
  4. If the 5 volt reference circuit is open or shorted to ground, repair it as necessary. Refer to Wiring Repairs or Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 12

Go to Step 7

7

  1. Check the 5 volt reference circuit for a poor connection at the PCM.
  2. If a problem is found, repair as necessary. Refer to Wiring Repairs or Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 12

Go to Step 11

8

  1. Turn the key 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 Wiring Repairs or Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Was a problem found and corrected?

--

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 or Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Was a problem found and corrected?

--

Go to Step 12

Go to Step 11

10

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

Is the action complete?

--

Go to Step 12

--

11

Important: The replacement PCM must be programmed.

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

Is the action complete?

--

Go to Step 12

--

12

  1. Clear DTCs with the scan tool.
  2. Turn the key to Off and wait 15 seconds.
  3. Operate vehicle within the conditions that are required for this diagnostic to run. Refer to Conditions for Running the DTC.

Does the scan tool indicate that this test ran and passed?

--

Go to Step 13

Go to Step 2

13

Review Captured Info using the scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to the applicable DTC table

System OK