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P0107










Electrical Diagram:






CIRCUIT DESCRIPTION

The Manifold Absolute Pressure (MAP) sensor is mounted to the rear of the intake manifold. The MAP sensor measures the pressure changes within the intake manifold which is an indication of the engine load. The MAP sensor has a 5.0 volt reference, a ground, and a signal circuit.

The MAP sensor contains a diaphragm which changes the resistance based on pressure. When the manifold pressure is low (high vacuum) the sensor output voltage is low. When the manifold pressure is high (low vacuum) the sensor output voltage is high.

The MAP sensor voltage (depending on altitude) can range from 1.0-1.5 volts at idle (high vacuum) to 4.0 - 4.9 volts at wide open throttle (low vacuum). When the PCM senses a signal voltage lower than the normal operating range of the sensor, this DTC will set.


CONDITIONS FOR SETTING THE DTC

^ No TP sensor DTCs set

^ TP Angle less than 26% when engine speed is greater than 1200 RPM

^ TP Angle is between 4-10% when the engine speed is less than 1200 RPM

^ MAP is less than 0.10 volts

^ All conditions met for greater than 2 seconds.


ACTION TAKEN WHEN THE DTC SETS

^ The PCM illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.

^ The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Freeze Frame and/or the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC

^ The PCM turns the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail.

^ A last test failed (current DTC) clears when the diagnostic runs and does not fail.

^ A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.

^ The PCM battery voltage is interrupted.

^ Use a scan tool in order to clear the MIL/DTC.

DIAGNOSTIC AIDS:

^ The following may cause an intermittent:

- Mis-routed harness

- Rubbed through wire insulation

- Broken wire inside the insulation

^ The PCM 5.0 volt reference circuits are internally connected within the PCM. If all the MAP sensor circuits are OK, inspect the following component/circuits for malfunctions:

- A/C Refrigerant Pressure sensor

- Fuel Level sensor (right side)

- Engine Oil Pressure sensor

^ For an intermittent, refer to Symptoms. Testing and Inspection

TEST DESCRIPTION

The numbers below refer to the step numbers on the diagnostic table.

2. If DTC P1635 sets at the same time, this indicates that the 5.0 voltage reference circuit is either shorted to a ground or shorted to a voltage. The 5.0 volt reference circuit is internally connected within the PCM. The A/C Refrigerant Pressure sensor, Engine Oil Pressure sensor, and the Fuel Level sensor (right side) may be causing this DTC to set. Refer to DTC P1635 for further diagnosis. P1635

3. This step determines if the malfunction is present.

4. Using the Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed.

5. If the scan tool displays 5.0 volts, the MAP sensor signal, 5.0 volt reference circuit, and the PCM are OK. For any test that requires probing the PCM or component harness connectors, use the Connector Test Adapter Kit J 35616-A. Using this kit will prevent any damage to the harness connector terminals.

6. If the scan tool displays 5.0 volts, the MAP sensor signal circuit and the PCM are OK. For any test that requires probing the PCM or component harness connectors, use the Connector Test Adapter Kit J 35616-A. Using this kit will prevent any damage to the harness connector terminals.

7. Disconnecting the PCM allows using the DMM J 39200 in order to check the continuity of the circuits. This aids in locating an open or a shorted circuit.

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