GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2002 🢒 Firebird 🢒 Body and Accessories 🢒 Body Control System 🢒 DTC P1107

Circuit Description

The manifold absolute pressure (MAP) sensor responds to pressure changes in the intake manifold. The pressure changes occur based on the engine load. The MAP sensor has the following circuits:

    • 5-volt reference circuit
    • Low reference circuit
    • MAP sensor signal circuit

The powertrain control module (PCM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit. The PCM also provides a ground on the low reference circuit. The MAP sensor provides a signal to the PCM on the MAP sensor signal circuit which is relative to the pressure changes in the manifold. The PCM should detect a low signal voltage at a low MAP, such as during an idle or a deceleration. The PCM should detect a high signal voltage at a high MAP, such as the ignition is ON, with the engine OFF, or at a wide open throttle (WOT). The MAP sensor is also used in order to determine the barometric pressure (BARO). This occurs when the ignition switch is turned ON, with the engine OFF. The BARO reading may also be updated whenever the engine is operated at WOT. The PCM monitors the MAP sensor signal for voltage outside of the normal range.

If the PCM detects a MAP sensor signal voltage that is intermittently low, DTC P1107 will set.

Conditions for Running the DTC
    • The ignition is ON.
    • DTCs P0606, P1120, P1125, P1220, P1221, P1271, P1272, P1273, P1275, P1276, P1280, P1281, P1285, P1286, P1514, P1515, P1516, P1517, or P1518 are not set.
    • The throttle angle is more than 0 percent when the engine speed is less than 1,000 RPM.
        OR
    • The throttle angle is more than 10 percent when the engine speed is more than 1,000 RPM.

Conditions for Setting the DTC

The MAP sensor signal voltage is less than 0.1 volt for more than 20 seconds.

Action Taken When the DTC Sets
    • The control module stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
    • The driver information center, if equipped, may display a message.

Conditions for Clearing the DTC
    • A current DTC Last Test Failed clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
    • Clear the DTC with a scan tool.

Test Description

The number below refers to the step number on the diagnostic table.

  1. The fault is currently not present. Many intermittent open or shorted circuits come and go with harness and connector movement that is caused by vibration, by engine torque, and by bumps. This step attempts to recreate the fault which set the DTC.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2
  1. Install a scan tool.
  2. Start the engine.
  3. Monitor the DTC Information using the scan tool.

Does the scan tool indicate that DTC P1635 or P0107 is current?

--

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3

With a scan tool observe the MAP sensor voltage.

Does the scan tool indicate that the voltage is less than the specified value?

0.1 V

Go to Step 5

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool , observe the MAP sensor voltage while moving the following components:
    4. • The MAP sensor
    • The PCM connector
    • The wiring harness that is related to the MAP sensor

Does the scan tool indicate that the MAP sensor voltage is less than the specified value and holding?

0.1 V

Go to Step 5

Go to Step 11

5
  1. Turn OFF the ignition.
  2. Disconnect the MAP sensor electrical connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground.

Does the voltage measure near the specified value?

5 V

Go to Step 6

Go to Step 7

6

Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the MAP sensor and the signal circuit of the MAP sensor.

Does the scan tool indicate that the voltage is near the specified value?

5 V

Go to Step 9

Go to Step 8

7

Test the 5-volt reference circuit of the MAP sensor for a short to ground or for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

8

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

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

9

Inspect for poor connections 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 11

Go to Intermittent Conditions

10

Inspect for poor connections at the PCM. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Intermittent Conditions

11
  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.

Does the DTC run, and pass?

--

Go to Step 12

Go to Step 2

12

With a scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK