P1107

Steps 1 - 7:

Steps 8 - 10:

DTC P1107 Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent Low Voltage




Circuit Description
The manifold absolute pressure (MAP) sensor responds to changes in intake manifold pressure. The MAP sensor signal voltage to the powertrain control module (PCM) varies from below 2 volts at idle (low manifold pressure) to above 4 volts with the ignition ON, engine not running or at wide-open throttle (high manifold pressure).

A "speed density" method of determining engine load is used on the 2.21 engine. This is calculated using inputs from the MAP sensor, the CKP sensor, and the Intake Air Temperature (IAT) sensor. The MAP sensor is the main sensor used in this calculation, and measuring engine load is its main function.

The MAP sensor is also used to determine manifold pressure changes while the linear EGR flow test diagnostic is being run, to determine engine vacuum level for some other diagnostics and to determine barometric pressure (BARO). Refer to DTC P0401.

The PCM compares the MAP sensor signal to a calculated MAP based on throttle position and various other engine load factors. If the PCM detects a MAP signal that is intermittently below the calculated value, DTC P1107 will set. DTC P1107 is a type D code.

Conditions for Setting the DTC
- No TP sensor Diagnostic Trouble Codes are present.
- Engine is running.
- Throttle angle is below 0% if engine speed is less than 1300 RPM.
- Throttle angle is below 5% if engine speed is above 1300 RPM.
- The MAP sensor indicates an intermittent manifold absolute pressure above 11 kPa for a total of approximately 5 seconds over a 16 - second period of time.

Action Taken When the DTC Sets
- The PCM will not illuminate the malfunction indicator lamp (MIL).
- The PCM will store conditions which were present when the Diagnostic Trouble Code was set as Failure Records data only. This information will not be stored as Freeze Frame data.

Conditions for Clearing the DTC
- A history Diagnostic Trouble Code P1107 will clear after 40 consecutive warm-up cycles have occurred without a fault.
- Diagnostic Trouble Code P1107 can be cleared by using the Scan Tool's "Clear Info" function.

Diagnostic Aids
Check for the following conditions:
- Poor connection at PCM - Inspect harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal-to-wire connection.
- The MAP sensor shares a 5 Volt Reference with the TP sensor and Fuel Pressure sensor. If these codes are also set, it could indicate a problem with the 5 Volt reference circuit.
- The MAP sensor shares a ground with the TP sensor and Fuel Pressure sensor.
- Damaged harness - Inspect the wiring harness for damage; shorts to ground, shorts to battery positive, and open circuits. If the harness appears to be OK, observe the MAP display on the Tech 2 while moving connectors and wiring harnesses related to the sensor. A change in the display will indicate the location of the fault.

Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the Diagnostic Trouble Code to be set occurs. This may assist in diagnosing the condition.