Heated/Cooled Seat Switch Indicator Malfunction

Heated/Cooled Seat Switch Indicator Malfunction

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.



Diagnostic Fault Information






Circuit/System Description

The driver and front passenger climate control seats are controlled by separate heated and cool seat switches. The switches are located on the door panels. When a heated or cool seat switch is pressed, ground is momentarily applied through the switch contacts and the switch signal circuit to the door module. In response to this signal, the module then sends a message to the memory seat module via the low speed GMLAN serial data line indicating the heat or cool seat request. The door module then applies voltage through the appropriate indicator control circuits to the heated seat switch illuminating the appropriate indicators.


Reference Information
Schematic Reference

Heated/Cooled Seat Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Heated/Cooled Seats Description and Operation (Heated/Cooled Seats Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Programming and Relearning (Programming and Relearning) for Scan Tool Information


Circuit/System Verification

1. Ignition ON with the heated and cooled seat OFF, the heated and cooled seat switch mode indicators should not be illuminated.
2. Ignition ON, use a scan tool to observe the appropriate Door Switch Seat Indicator Cmd. parameter while pressing the heated seat switch. The reading should change between Off and On.



Circuit/System Testing


Heated and Cooled Seat Switch Indicators Inoperative
1. Ignition OFF, disconnect the X4 harness connector at the door module.
2. Connect a 3A fused jumper wire between the low reference circuit terminal 4 and ground.
3. Connect a test lamp between each indicator control circuit and battery voltage. Each indicator should illuminate when tested.

• If any indicator does not illuminate, replace the heated and cooled seat switch.

4. If all indicators illuminate, replace the door module.




Heated and Cooled Seat Switch Indicators Always On
1. Ignition OFF, disconnect the X4 harness connector at the door module.
2. Ignition ON, the heated and cooled seat switch mode indicators should not be illuminated.

• If illuminated, test the control circuit of the illuminated indicator for a short to voltage.

3. If all circuits test normal, replace the door module.



Repair Instructions

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

* Heated and Cooled Seat Switch Replacement (Service and Repair)
* Programming and Relearning (Programming and Relearning) for door module replacement, setup, and programming