GM Service Manual Online
For 1990-2009 cars only

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 engine control module (ECM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit. The ECM provides a ground on the low reference circuit. The MAP sensor provides a signal to the ECM on the MAP sensor signal circuit which is relative to the pressure changes in the manifold. The ECM detects a low signal voltage at a low MAP, such as during an idle or a deceleration. The ECM detects 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 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 MAP sensor contains the following circuits:

    • A 5-volt reference
    • A low reference
    • A MAP sensor signal

If the ECM detects that the MAP sensor pressure/voltage is too low, DTC P0107 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0107 Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage.

Conditions for Running the DTC

The ignition is ON with the engine OFF.

The ignition 1 voltage is more than 10 volts.

Or

The ignition 1 voltage is more than 10 volts.

The throttle is in the closed position.

The engine speed is less than 1,500 RPM.

Or

The ignition 1 voltage is more than 10 volts.

The engine speed is between 1,500-5,500 RPM.

The TP angle is more than 10.3 degrees.

DTC P0107 runs continuously once the above conditions are met.

Conditions for Setting the DTC

The ECM detects that the MAP is less than 16 kPa or 0.142 volts for more than 2 seconds.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • 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 emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

    • If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, the other 5-volt reference circuits may be affected.
    • For an intermittent condition, refer to Intermittent Conditions .

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check - Engine Controls?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Start the engine.
  2. Allow the engine to reach the normal operating temperature.
  3. Observe the DTC Information with a scan tool.

Did DTC P0107 fail this ignition?

--

Go to Step 4

Go to Step 3

3

  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Did the DTC fail this ignition?

--

Go to Step 4

Go to Diagnostic Aids

4

  1. Turn OFF the ignition.
  2. Disconnect the manifold absolute pressure (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.

Is the voltage within the specified range?

4.8-5.2 V

Go to Step 5

Go to Step 6

5

  1. Connect a 3-amp fused jumper wire between the 5-volt reference circuit and the signal circuit of the MAP sensor.
  2. Observe the MAP sensor parameter with a scan tool.

Is the pressure more than the specified value?

102 kPa

Go to Step 8

Go to Step 7

6

Important: The 5-volt reference circuits are internally and externally connected at the ECM. Other component DTCs may be set. If other DTCs are set, review the electrical schematic and diagnose the applicable circuits and components.

Test the 5-volt reference circuit of the MAP sensor for the following conditions:

    • An open
    • A short to ground
    • High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

7

Test the signal circuit of the MAP sensor for the following conditions:

    • An open
    • A short to ground
    • High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

8

Test for an intermittent and 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 12

Go to Step 10

9

Test for an intermittent and for a poor connection at the engine control module (ECM). 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 12

Go to Step 11

10

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

Did you complete the replacement?

--

Go to Step 12

--

11

Replace the ECM. Refer to Engine Control Module Replacement .

Did you complete the replacement?

--

Go to Step 12

--

12

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 13

13

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK