Rear Seat Heater Switch Indicator Malfunction
Rear Seat Heater 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 left and right rear passenger heated seats are controlled by separate heated seat switches. The switches are located on the rear door panels. When a heated seat switch is pressed, ground is momentarily applied through the switch contacts and the switch signal circuit to the rear heated seat module. In response to this signal, the module then applies battery voltage through the element supply voltage circuits to the seat cushion and seat back heating elements. The heated seat module then supplies a ground 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
Rear Heated Seats Description and Operation (Rear Heated 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 Testing
Rear Heated Seat Switch Indicators Inoperative
1. Ignition OFF, disconnect the harness connector at the heated seat switch.
2. Ignition ON, verify that a test lamp illuminates between the supply voltage circuit terminal K and ground.
• If the test lamp does not illuminate, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the body control module (BCM).
3. Ignition OFF, connect the harness connector to the heated seat switch.
4. Disconnect the appropriate harness connector X3 or X4 at the rear heated seat module.
5. Ignition ON, connect a test lamp between the inoperative heated seat switch indicator control circuit and ground. The indicator should illuminate.
• If the indicator does not illuminate, test the indicator control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, test or replace the heated seat switch.
6. If all circuits test normal, replace the heated seat module.
Heated Seat Switch Indicators Always On
1. Ignition OFF, disconnect the X3, X4 harness connector at the rear heated seat module.
2. Ignition ON, the heated seat switch mode indicators should not be illuminated.
• If illuminated, test the control circuit of the illuminated indicator for a short to ground. If the circuit tests normal, test or replace the heated seat switch.
3. If all circuits test normal, replace the rear heated seat module.
Component Testing
Rear Heated Seat Switch
1. Ignition OFF, disconnect the harness connector at the heated seat switch switch.
2. Test for infinite resistance between the signal terminal G and the ground terminal J with the switch in the open position.
• If less than infinite, replace the heated seat switch switch.
3. Test for infinite resistance between the signal terminal A and the ground terminal J with the switch in the open position.
• If less than infinite, replace the heated seat switch switch.
4. Test for less than 5 ohms between the signal terminal G and the ground terminal J with the switch in the closed position.
• If greater than 5 ohms, replace the heated seat switch.
5. Test for less than 5 ohms between the signal terminal A and the ground terminal J with the switch in the closed position.
• If greater than 5 ohms, replace the heated seat switch.
6. Connect a 3A fused jumper wire between the heated seat switch supply voltage terminal K and battery voltage.
7. Connect a test lamp between the following indicator control circuits and ground. The selected indicator should illuminate.
* Terminal B seat back only mode indicator
* Terminal C low heat indicator
* Terminal D medium heat indicator
* Terminal E high heat indicator
* Terminal H seat back cushion mode indicator
• If any of the indicators do not illuminate, replace the rear heated seat switch.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Rear Seat Heater Switch Replacement (Rear Seat Heater Switch Replacement)
* Programming and Relearning (Programming and Relearning) for heated seat module and BCM replacement, setup, and programming