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P1762




DTC P1762

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 Instructionsprovides an overview of each diagnostic category.

DTC Descriptor
DTC P1762
- Transmission Mode Switch Signal Message

Circuit/System Description

The body control module (BCM) is constantly sending the engine control module (ECM) and transmission control module (TCM) serial data messages with information regarding transmission mode switch activation. The TCM sets this code when it detects a discrepancy in the structure of the message causing the signal message 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 speed is 400 RPM or greater for 5 seconds.
* No other CAN errors are present.

Conditions for Setting the DTC

The TCM detects an error in the rolling count value that does not match with the BCM.

Action Taken When the DTC Sets

* DTC P1762 is a Type C DTC.
* The TCM inhibits TAP Shift operation.

Conditions for Clearing the DTC

DTC P1762 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 P1762 is an informational DTC. Diagnose all other transmission control DTCs prior to DTC P1762. Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. If there are no other transmission 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.