P0108

DTC P0108

CIRCUIT DESCRIPTION

With Supercharger/RPO L32
The MAP sensor responds to changes in intake manifold pressure which gives an indication of the engine load. The MAP sensor wiring includes a 5-volt reference circuit, a low reference circuit, and a signal circuit. The PCM supplies 5 volts to the MAP sensor on the 5-volt reference circuit, and 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. With low MAP, such as during idle or deceleration, the PCM should detect a low MAP sensor signal voltage. With high MAP, such as WOT, the PCM should detect a high MAP sensor signal voltage. This MAP sensor will indicate pressure between 8-208 kPa. 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 excessively high, DTC P0108 sets.

CONDITIONS FOR RUNNING THE DTC
- DTCs P0068, P0120, P0220, P1125, P1516, P1518, P2101, P2107, P2108, P2119, P2120, P2125, P2135, P2138 are not set.
- The engine has been running for a length of time that is determined by the start-up coolant temperature. The length of time ranges from 2 minutes at less than -30°C (-22°F) to 1 second at more than 30°C (86°F).
- The throttle angle is less than 2 percent when engine speed is less than 1,000 RPM.

OR

- The throttle angle is less than 10 percent when the engine speed is more than 1,000 RPM.

CONDITIONS FOR SETTING THE DTC
The PCM detects that the MAP sensor signal voltage is more than 4.3 volts for 7 seconds.

ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction A 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.

TEST DESCRIPTION

Steps 1-9:

Steps 10-16:

The numbers below refer to the step numbers on the diagnostic table.
5. The MAP sensor, the exhaust gas recirculation (EGR) valve, and the fuel tank pressure (FTP) sensor utilize the 5-volt reference A circuit for supply voltage. DTC P0641 sets if a failure occurs causing this system voltage to be pulled high or low. This DTC should be diagnosed first.
9. A short to voltage on the MAP sensor signal circuit may backfeed through the sensor affecting the 5-volt reference system voltage. This step tests for this condition.