GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptors

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

DTC P0108: Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

5-Volt Reference

P0107, P0405, P0452, P0462, P0532, P0641

P0106, P0107

P0107

P0108, P0453, P0533, P0641

P0106, P0107

MAP Sensor Signal

P0107

P0106, P0107

P0107

P0108

P0106, P0107

Low Reference

--

P0106, P0107

P0106, P0108, P1101

--

P0106, P0108

Typical Scan Tool Data

MAP Sensor

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Engine running, transmission in Park or Neutral

Parameter Normal Range: 12-48 kPa (Varies with altitude)

5-Volt Reference

10 kPa

10 kPa

104 kPa

MAP Sensor Signal

10 kPa

10 kPa

104 kPa

Low Reference

--

80-103 kPa

--

Circuit/System Description

The manifold absolute pressure (MAP) sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The powertrain control module (PCM) supplies 5 volts to the MAP sensor on a 5-volt reference circuit and provides a ground on a low reference circuit. The MAP sensor provides a voltage signal to the PCM on a signal circuit relative to the intake manifold pressure changes.

Conditions for Running the DTC

P0107

    • DTCs P0068, P0120, P0220, P1516, P2101, P2108, P2120, P2125, P2135, or P2138 are not set
    • The ignition is ON.
    • The throttle angle is greater than 0 percent, if the engine speed is less than 1,000 RPM.
        OR
    • The throttle angle is greater than 10 percent, if the engine speed is greater than 1,000 RPM.
    • The DTC runs continuously when the above conditions are met.

P0108

    • DTCs P0068, P0120, P0220, P1516, P2101, P2108, P2120, P2125, P2135, or P2138 are not set.
    • The engine has been running for a length of time that is determined by the startup coolant temperature. The length of time ranges from 5.5 minutes at less than -30°C (-22°F) to 10 seconds at more than +30°C (+86°F).
    • The throttle angle is less than 2 percent when the engine speed is less than 3,000 RPM.
        OR
    • The throttle angle is more than 30 percent when the engine speed is greater than 3,000 RPM.
    • The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

P0107

    • The control module detects that the MAP sensor voltage is less than 0.1 volt for more than 3 seconds.
    • This diagnostic runs continuously.

P0108

    • The control module detects that the MAP sensor voltage is more than 4.3 volts for more than 3 seconds.
    • This diagnostic runs continuously.

Action Taken When the DTC Sets

DTCs P0107 and P0108 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0107 and P0108 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

    • J 23738-A Mityvac
    • J 35555 Metal Mityvac

Circuit/System Testing

Important: All electrical components and accessories must be turned OFF, and allowed to power down.

  1. Ignition OFF, disconnect the harness connector at the MAP sensor.
  2. Ignition OFF for 90 seconds, test for less than 5 ohms between the low reference circuit terminal A and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the PCM.
  4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.
  5. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the PCM.
    If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the PCM.
  6. Verify the scan tool MAP Sensor parameter is less than 12 kPa.
  7. If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the PCM.
  8. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal C. Verify the scan tool MAP Sensor parameter is greater than 103 kPa.
  9. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the PCM.
  10. If all circuits test normal, test or replace the MAP sensor.

Component Testing

  1. Turn ON the ignition, with the engine OFF, and remove the MAP sensor.
  2. Install a 3A fused jumper wire between the 5-volt reference circuit terminal C and the corresponding terminal of the MAP sensor.
  3. Install a jumper wire between the low reference circuit terminal A of the MAP sensor and ground.
  4. Install a jumper wire at terminal B of the MAP sensor.
  5. Connect a DMM between the jumper wire from terminal B of the MAP sensor and ground.
  6. Install the J 23738-A or J 35555 to the MAP sensor vacuum port. Slowly apply vacuum to the sensor while observing the voltage on the DMM. The voltage should vary between 0-5.2 volts, without any spikes or dropouts.
  7. If the voltage is not within the specified range or is erratic, replace the MAP sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Manifold Absolute Pressure Sensor Replacement
    •  Control Module References for PCM replacement, setup, and programming