Service Information

Orlando

DTC P150C

Diagnostic Instructions

•	Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

•	Review Strategy Based Diagnosis for an overview of the diagnostic approach.

•	Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

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

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 is running.

•	No other CAN errors are present.

Conditions for Setting the DTC

The ECM detects greater than 2 message count errors.

Action Taken When the DTC Sets

•	The ECM Disables engine speed requests from transmission.

•	DTC P150C is a Type B DTC.

•	The TCM commands maximum line pressure during shifts.

Conditions for Clearing the DTC

DTC P150C is a Type B DTC.

Reference Information

Description and Operation

Data Link Communications Description and Operation

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

•	DTC P150C is an informational DTC. Diagnose all other Engine Control DTCs prior to DTC P150C. Refer to Diagnostic Trouble Code (DTC) List - Vehicle .

•	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 .

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for control solenoid valve assembly replacement, set-up, and programming.