Front Heated Seat Malfunction
Front Heated Seat Malfunction
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 Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The driver and passenger heated seats are controlled by separate heated seat switches that are located in the HVAC control module. Engine ON, when a heated seat switch is pressed, a serial data message is sent from the HVAC control module to the seat heating control module control module indicating the heated seat command. In response to this message, the seat heating control module applies battery positive voltage through the element supply voltage circuit to the appropriate seat heating elements. The seat heating control module then sends a serial data message back to the HVAC control module to either illuminate or turn off the appropriate temperature indicator.
Reference Information
Schematic Reference
Heated/Cooled Seat Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Description and Operation
Heated Seats Description and Operation Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify that no heated seat DTCs are set.
• If any heated seat DTC is set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
• If no heated seat DTCs are set
3. Engine ON.
4. Verify the scan tool Front Seat Heating Control Module Driver Seat Heating/Venting/Cooling Mode parameter changes between Off and Back & Cushion Heat after pressing the driver heated seat switch.
• If the parameter does not change
Replace the K33 HVAC control module.
• If the parameter changes
5. Verify the scan tool Passenger Front Seat Heating/Venting/Cooling Mode Switch parameter changes between Off and Back & Cushion Heat after pressing the passenger heated seat switch.
• If the parameter does not change
Replace the K33 HVAC control module.
• If the parameter changes
6. Replace the K29 seat heating control module.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Heater and Air Conditioning Control Replacement Service and Repair
* Control Module References Control Module References for seat heating control module replacement, programming and setup