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Rear Heated Seat Malfunction

Rear Heated Seat Malfunction

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.


Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
Left Rear Heated Seat Element Control Terminal 3 X2 B242A 02 B2425 0D B242A 01 B2425 0B, B2425 0E
Left Rear Heated Seat Element Control Terminal 1 X2 B242A 02 B2425 0D B242A 01 B2425 0B, B2425 0E
Left Rear Heated Seat Temperature Sensor Signal B1925 02 B1925 05 B1925 05 B2345 13
Left Rear Heated Seat Temperature Sensor Low Reference - B1925 05 - B2345 13
Right Rear Heated Seat Element Control Terminal 5 X2 B242A 02 B2430 0D B242A 01 B2430 0B, B2430 0E
Right Rear Heated Seat Element Control Terminal 2 X2 B242A 02 B2430 0D B242A 01 B2430 0B, B2430 0E
Right Rear Heated Seat Temperature Sensor Signal B2170 02 B2170 05 B2170 05 B2345 13
Right Rear Heated Seat Temperature Sensor Low Reference - B2170 05 - B2345 13


Circuit/System Description

The heated seat system is designed to operate with the engine ON. The left and right rear heated seat switches are located in the face plate of the rear audio control module. The rear seat heating control module located under the seat cushion (40 % side), controls the heated seat operation for both rear seats. When a heated seat switch is pressed, a serial data message is sent from the rear audio control module to the rear seat heating control module indicating the heated seat command. In response to this message, the rear seat heating control module applies battery positive voltage through the heater element supply voltage circuit and ground through the low side control circuit to the seat heating elements. The seat heating control module then sends a serial data message back to the rear audio control module to illuminate the appropriate seat temperature indicator.

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Rear Heated Seats Description and Operation

Electrical Information Reference


• Circuit Testing

• Connector Repairs

• Testing for Intermittent Conditions and Poor Connections

• Wiring Repairs


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification


1. Engine ON, observe the scan tool Left Rear Seat Heating/Venting/Cooling Mode parameter while pressing the left rear HEATED seat switch. The reading should change between Off and Back & Cushion Heat.

2. If not the specified value, replace the A13 rear audio control module.

3. Observe the scan tool Right Rear Seat Heating/Venting/Cooling Mode parameter while pressing the right rear HEATED seat switch. The reading should change between Off and Back & Cushion Heat.

4. If not the specified value, replace the A13 rear audio control module.

5. If all scan tool parameter readings test normal, there are no DTCs set, and the left and/or right rear heated seat is inoperative, replace the K29R rear seat heating control module.


Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.


• Heater and Air Conditioning and Radio Control Module Replacement

• Control Module References for K29 rear seat heating control module and A13 rear audio control module replacement, setup, and programming