For 1990-2009 cars

### 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 P1761: Up and Down Shift Switch Signal Circuit

### Circuit/System Description

The TAP Shift Switch Signal system allows the driver to manually shift gears by using the Upshift and Downshift positions located on the automatic transmission shift Lever. When TAP mode is selected, the shift switch input signals to the body control module (BCM). This code sets when the rolling count of the TCM does not match the same value sent from the BCM.

### Conditions for Running the DTC

The engine run time is greater than 5 seconds.

### 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 P1761 is a Type C DTC.

• | The TCM disables TAP Shift operation.

### Conditions for Clearing the DTC

DTC P1761 is a Type C DTC.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Description and Operation

Electronic Component Description

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Testing

Ignition ON, attempt to establish communication with the BCM with a scan tool.

⇒ | If no communication with the BCM, refer to Control Module References for further diagnosis.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup,and programming.