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 provides 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

Open/High Resistance

Short to Voltage

Signal Performance

5-Volt Reference

P0107, P0697

P0107, P0106

P0108, P0697

P0106

MAP Sensor Signal

P0107

P0107, P0106

P0108

P0106

Low Reference

--

P0108, P0106

--

P0106

Typical Scan Tool Data

MAP Sensor

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Engine operating in Closed Loop, idling, and accessories OFF.

Parameter Normal Range: 26-52 kPa

5-Volt Reference

0 kPa

0 kPa

127 kPa

MAP Sensor Signal

0 kPa

0 kPa

127 kPa

Low Reference

--

127 kPa

--

Circuit/System 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).

Conditions for Running the DTC

    • The ignition is ON, or the engine is running.
    • The DTCs run continuously when the above condition is met.

Conditions for Setting the DTC

P0107

The ECM detects that the MAP sensor signal is less than 3.5 kPa for greater than 5 seconds.

P0108

The ECM detects that the MAP sensor signal is greater than 115 kPa for greater than 5 seconds.

Action Taken When the DTC Sets

    • DTC P0107 and P0108 are Type B DTCs.
    • The BARO will not be updated.

Conditions for Clearing the DTC

DTC P0107 and P0108 are Type B DTCs.

Diagnostic Aids

If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the scan tool parameters for the component. The scan tool parameters will change abruptly if there is a condition with the circuit or a connection.

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 Vacuum Pump
    • J 35555 Metal Mity-vac

Circuit/System Verification

  1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0697 is not set.
  2. If P0697 is set, refer to DTC P0641, P0651, P0697, or P06A3.
  3. Engine running, observe the scan tool MAP Sensor parameter. The reading should be between 26-52 kPa.
  4. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the MAP sensor.
  2. Ignition OFF for 1 minute, test for less than 5 Ω between the low reference circuit terminal 2 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 ECM.
  4. Ignition ON, test for 4.8-5.2 V between the 5-volt reference circuit terminal 1 and ground.
  5. If less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the ECM.
    If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  6. Verify the scan tool MAP sensor parameter is 0.00 V.
  7. If greater than the specified value, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the ECM.
  8. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5-volt reference circuit terminal 1. Verify the scan tool MAP sensor parameter is 127 kPa.
  9. If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
  10. If all circuits test normal, test or replace the MAP sensor.

Component Testing

The ignition ON, engine OFF MAP sensor scan tool value should decrease within +/- 4 kPa by the amount of vacuum applied with the J 23738-A or J 35555 . For example, at 92 kPa, the MAP sensor scan tool reading should be between 71-79 kPa with 5 in Hg (17 kPa) of vacuum applied to the sensor.

Ignition ON, Engine OFF, MAP Sensor Parameter

MAP Sensor Parameter With 5 Inches of Vacuum Applied

MAP Sensor Parameter With 10 Inches of Vacuum Applied

100

79-87

62-70

90

69-77

52-60

80

59-67

42-50

70

49-57

32-40

60

39-47

22-30

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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