P0107

Circuit Description
The Manifold Absolute Pressure (MAP) sensor is a pressure sensor. The Control Module (PCM/VCM) supplies the MAP sensor a reference voltage, signal, and ground circuits. When manifold vacuum is low, the MAP sensor signal voltage rises to a value near the reference voltage, and the MAP sensor signal voltage decreases when the manifold vacuum increases. The Control Module monitors the MAP sensor signal circuit voltage in order to calculate the vacuum within the intake manifold.

Certain vehicle models will also use the MAP sensor in order to calculate the barometric pressure when the ignition switch is turned ON and the engine is NOT cranked. This BARO reading may also be updated whenever the engine is operated at Wide Open Throttle.
This DTC is designed to detect MAP signal voltages lower than possible in a normally operating MAP sensor.

Conditions for Running the DTC
^ No active TP sensor DTCs
^ The engine is running
^ The throttle position is more than 0 percent with an engine speed below 800 RPM
OR
The throttle position is more than 12.5 percent with an engine speed above 800 RPM

Conditions for Setting the DTC
The MAP voltage is below 0.04 volts for more than 1 second.

Action Taken When the DTC Sets
^ The Control Module illuminates the Malfunction Indicator Lamp (MIL) if a failure is detected during 2 consecutive key cycles.
^ The Control Module will set the DTC and records the operating conditions at the time the diagnostic fails. The Control Module stores the failure information in the scan tools Freeze Frame and/or the Failure Records.

Conditions for Clearing the MIL/DTC
^ The Control Module turns OFF the MIL after 3 consecutive drive trips when the test has Run and Passed.
^ A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles (coolant temperature has risen 22°C (40°F) from the start-up coolant temperature and the Engine Coolant Temperature is more than 70°C (158°F) during the same ignition cycle).
^ Use the scan tool Clear Information function.

Diagnostic Aids
An intermittent open in the MAP sensor signal circuit or the 5 volt reference circuit could result in a DTC P1107.

With the ignition ON and the engine OFF, the manifold pressure is equal to the atmospheric pressure with the signal voltage high. The VCM uses this information as an indication of the altitude of the vehicle.

Comparison of this reading with a known good vehicle using the same sensor is a good way to check the accuracy of a suspect sensor. Readings should be the same kPa. Refer to Symptoms. Symptom Related Diagnostic Procedures

Important: After removing the MAP sensor from the intake manifold, replace the MAP sensor to the intake manifold seal.

Remove the MAP sensor. Twist the sensor by hand (only) in order to check for intermittent connections. Output changes of more than 0.1 volt indicate a bad connector or connection.

An intermittent may be caused by any of the following conditions:
^ A poor connection
^ Rubbed through wire insulation
^ A broken wire inside the insulation

Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Refer to Intermittents and Poor Connections Diagnosis.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step determines if DTC P0107 is the result of a hard failure or an intermittent condition.
3. This step determines if the VCM is able to provide a 5 volt reference to the MAP sensor.
4. The scan tool may not display 5 volts. The Important thing is that the VCM recognized the voltage as more than 4 volts, indicating that the VCM and MAP signal circuits are OK.
10. The 5 volt reference of the VCM supply is shared by the MAP, FTP, TP, and EGR position sensors. A short to ground at ANY of the sensors 5 volt reference circuits OR an internally shorted sensor may cause this DTC to set.
14. The sensor connectors must remain disconnected while the VCM C3 connector remains connected for this step. The VCM terminals C3 12 and C3 27 are spliced together inside the VCM. When checking the 5 volt reference circuit for a short to ground, both the 5 volt reference circuits must be checked.