Winter mode programming in the transmission control module (TCM) will allow the driver selection of a third gear start in order to reduce wheel spin under low traction conditions. The winter mode switch is a console mounted momentary contact switch located on the electronic PRNDL assembly. Accessory voltage is supplied to the electronic PRNDL assembly through the ELEC PRNDL fuse. When the winter mode switch is depressed, it momentarily contacts the switch signal circuit. The rear integration module (RIM) recognizes the voltage on the circuit and sends a class 2 serial data message to the dash integration module (DIM). The DIM sends a class 2 message to the engine control module (ECM). The ECM sends a request to the TCM through the controller area network (CAN) to enable the winter mode program.

The TCM evaluates the request, and if operating conditions are correct for enabling the program, the TCM sends a confirmation message to the ECM. The ECM then requests the instrument panel cluster (IPC) to illuminate the winter mode indicator.

The winter mode feature remains enabled until the mode switch is pressed again, the transmission is placed in a lower gear, and certain vehicle speed, transmission fluid temperature, or accelerator pedal positions are exceeded. Once disabled, the TCM will resume a normal shift pattern.

The TCM detects that the Winter Mode Switch has been continuously activated for 10 minutes.

DTC P1763 is a Type C DTC.

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, engine OFF. While observing the winter mode indicator on the IPC, press the winter mode switch several times. Does the winter mode indicator illuminate On and Off with switch operation?

⇒	Test the instrument panel cluster (IPC) for proper operation and lamp illumination. Refer to Diagnostic System Check - Vehicle .

⇒	Test the rear integration module (RIM) for proper winter mode switch input and output operation. Refer to Control Module References .

⇒	If the DTC resets, go to Circuit/System Testing.

2. 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 observed from the Freeze Frame/Failure Records data.

Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition ON, engine OFF. While observing the winter mode indicator on the IPC, press the winter mode switch several times. Is the winter mode indicator always ON?

⇒	Test the accessory voltage circuit for an open.

⇒	Test the winter mode switch signal circuit for an open.

⇒	Test the electronic PRNDL ground circuits for on open.

⇒	Replace the electronic PRNDL assembly.

2. While observing the winter mode indicator on the IPC, disconnect the electronic PRNDL assembly from the console wiring harness connector. Is the winter mode indicator still illuminated?

⇒	Replace the electronic PRNDL assembly.

3. Test the winter mode switch signal circuit for a short to ground. If the circuit test good replace the winter mode switch.

1. Disconnect the electronic PRNDL assembly.
2. Connect a DMM, between the winter mode switch signal circuit and the ground circuit of the electronic PRNDL assembly.
3. Set the DMM to measure resistance. While observing the DMM, press the winter mode switch several times. Does the resistance toggle between very low resistance to very high resistance as the switch is pressed?

⇒	Replace the electronic PRNDL assembly.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Manual Shift Detent Lever with Shaft Position Switch Assembly Replacement