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P150C




DTC P150C

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptor
DTC P150C
- Transmission Control Module Engine Speed Request Signal Message Counter Incorrect

Circuit/System Description

To improve vehicle shift feel, the transmission control module (TCM) is constantly sending the engine control module (ECM) serial data messages with information regarding its request for modifying engine speed or torque. The ECM sets this code when it detects a discrepancy in the structure of this message causing its integrity to be questioned.

An intermittent fault in the controller area network (CAN) circuits will cause DTC P150C to set.

Conditions for Running the DTC

* The engine run time is greater than 5 seconds.
* No other CAN errors are present.

Conditions for Setting the DTC

* DTC P150C is a Type B DTC.
* An intermittent fault in the CAN circuits.

Action Taken When the DTC Sets

* DTC P150C is a Type B DTC.
* The TCM commands maximum line pressure during shifts, which results in very harsh shifts.

Conditions for Clearing the DTC

DTC P150C is a Type B DTC.

Reference Information
DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)

Circuit/System Verification

1. DTC P150C is an informational DTC. Diagnose all other Engine Control DTCs prior to DTC P150C. Refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle).
2. If there are no other Engine Controls DTCs, diagnosis is accomplished by looking for an intermittent CAN circuit fault. Refer to Scan Tool Does Not Communicate with High Speed GMLAN Device (Scan Tool Does Not Communicate with High Speed GMLAN Device).