P1106

Circuit Description

The Manifold Absolute Pressure (MAP) sensor responds to changes in intake manifold pressure (vacuum). The MAP sensor signal voltage to the PCM varies from below 2.0 volts at idle (high vacuum) to above 4.0 volts with the key on, engine not running or at wide-open throttle (low vacuum).

The MAP sensor is used to determine manifold pressure changes while the linear EGR flow test diagnostic is being run (refer to DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient), to determine engine vacuum level for some other diagnostics and to determine barometric pressure (BARO). The PCM monitors the MAP signal for voltages outside the normal range of the MAP sensor. If the PCM detects a MAP signal voltage that is intermittently high, DTC P1106 will be set. P0401

Conditions for Running the DTC

^ No TP sensor DTC(s) are present.
^ Ignition on.
^ Throttle angle is steady below 30% if engine speed is below 3000 RPM.
^ Throttle angle is steady below 5% if engine speed is above 3000 RPM.

Conditions for Setting the DTC

^ The MAP sensor indicates an intermittent manifold absolute pressure above 90 kPa.
^ Above conditions for over 10 seconds.

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 DTC set as Fail Records data only. This information will not be stored as Freeze Frame data.

Conditions for Clearing the MIL/DTC

^ A history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ DTC can be cleared by using a scan tool.

Diagnostic Aids

Check for the following conditions:

^ Monitor the MAP sensor using the scan tool. If the MAP sensor does not respond to throttle changes, check the 3X circuits from the ignition control module to the PCM.
^ If the 3X signal is lost the PCM will only update the MAP sensor reading once per key cycle, when the engine is first started.
^ Depending on where the MAP sensor voltage (high voltage or low voltage) is when the engine is started, the high or low voltage MAP sensor DTC's will set.

Important: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.

^ Poor terminal connection.
Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Use a corresponding mating terminal to test for proper tension. Refer to Diagrams.
^ Damaged harness.
Inspect the wiring harness for damage. If the harness appears to be OK, observe the sensor display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the sensor display may indicate the location of the fault.
^ Inspect the PCM and the engine grounds for clean and secure connections.

If the DTC is determined to be intermittent, reviewing the Fail Records can be useful in determining when the DTC was last set.