Automatic Transmission - 4T45-E

DTC P1761

Diagnostic Instructions

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

DTC Descriptor
DTC P1761
- Up and Down Shift Switch Signal Circuit

Circuit/System Description

The controller area network (CAN) serial data bus is used by the body control module (BCM) and automatic transmission control module (TCM) to share information. This diagnostic applies to an invalid CAN signal.

Conditions for Running the DTC

The engine is running for at least 2 seconds.

Conditions for Setting the DTC

An error in the BCM Tap-up, Tap-down Signal Circuit count.

Action Taken When the DTC Sets

The TCM disables TAP shift operation.

Conditions for Clearing the DTC

DTC P1761 is a Type C DTC.

Diagnostic Aids

A BCM error is the only condition that will set this DTC.

Reference Information
Schematic Reference

Automatic Transmission Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Body Control System Description and Operation (Description and Operation)
DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observe from the Freeze Frame/Failure Records data.

If DTC resets replace BCM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for BCM replacement, setup, and programming.