The drive motor generator power inverter module (PIM) contains two motor control modules (MCM). Each MCM controls and monitors its respective drive motor generator based upon commands from the hybrid powertrain control module (HPCM). In order for the HPCM to monitor the internal combustion engine speed, MCM 1 is electrically connected to the crankshaft position sensor (CKP) signal and reference circuits. The MCM 1 engine speed information is broadcast to the HPCM over an internal PIM communication circuit. Additionally, the HPCM receives a GM LAN engine speed that is broadcast by the engine control module (ECM) and is based upon the ECM connection to the CKP sensor.

A drive motor generator position sensor is monitored by each motor control module (MCM). Each MCM monitors the angular position, speed and direction of its respective drive motor generator based upon the signals of the resolver-type position sensor.

The HPCM mathematically calculates what engine speed should be based upon the current transmission ratio and the drive motor generator speeds indicated by the drive motor generator position sensors.

The HPCM compares this mathematically calculated engine speed to the sensor-derived GM LAN ECM engine speed signal and MCM CKP signal engine speed. If the drive motor generator position sensor speeds are correct, the mathematical equation should accurately calculate engine speed. If the mathematical calculation for engine speed does not match the sensor-derived engine speed, a drive motor position speed sensor error is assumed and this DTC will set.

Condition 1

Condition 2

Condition 1

The difference between GM LAN ECM or MCM 1 CKP engine speed and HPCM calculated engine speed is greater than 1499 RPM for 1 second.

Condition 2

The difference between GM LAN ECM or MCM 1 CKP engine speed and HPCM calculated engine speed is greater than 249 RPM for 1 second.

Any condition that allows the engine or drive motor speed sensors to indicate their actual speed incorrectly may cause this DTC to set.

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Important: Diagnose ECM DTCs P0335 and P0336 prior to performing this procedure.

1. Clear the DTC information.
2. Turn the ignition OFF for 1 minute.
3. Attempt to start the engine.
4. Retest for DTC P0C2F.

Important: Diagnose ECM DTCs P0335 and P0336 prior to performing this procedure.

1. Repair the following conditions if observed:

•	ECM CKP sensor DTCs

Important: If mechanical binding of the engine is observed, internal transmission damage may have resulted when drive motor 1 attempted to crank the seized engine.

•	Mechanical condition which would cause drive motor 1 to rotate without a corresponding rotation of the engine.

2. Ignition ON, retest for DTC P02CF.

⇒	If the DTC resets, test each drive motor generator position sensor for proper operation. Refer to DTC P1B03 or P1B04.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.