Test D: DTC B12AC/B12AE - Drivers/Passenger Heated Seat Relay Drive Circuit Open Or Shorted To Ground

PINPOINT TEST D: DTC B12AC/B12AE - DRIVERS/PASSENGER HEATED SEAT RELAY DRIVE CIRCUIT OPEN OR SHORTED TO GROUND

Normal Operation
With the engine running and a heated seat button is pressed ON, the HVAC module supplies a switched ground output to the driver or passenger heated seat relay to energize the relay coil and operate the driver or passenger heated seat. The HVAC module monitors the output circuits CHS29 (WH/BU) (driver) and CHS30 (GY/YE) (passenger) for faults. If circuit CHS29 (WH/BU) (driver) or CHS30 (GY/YE) (passenger) is shorted to ground, HVAC DTC B12AC (driver seat) or B12AE (passenger seat) will set. If a short to ground condition exists on the output circuit, the seat may continue to heat after being switched off. If DTC B12AC or B12AE is set and the affected seat is inoperative, GO to Pinpoint Test B (driver seat) or GO to Pinpoint Test C (passenger seat) to diagnose the fault. Test B: The Heated Seat Is Inoperative/Does Not Operate Correctly - Driver Test C: The Heated Seat Is Inoperative/Does Not Operate Correctly - Passenger

- DTC B12AC Drivers Heated Seat Relay Drive Circuit Open or Shorted to Ground - If the driver heated seat relay drive circuit CHS02 (YE/BU) is open or shorted to ground and the HVAC module attempts to activate the driver heated seat relay, the DTC will set and the seat will fail to heat (circuit open) or may be on at all times (circuit shorted to ground) until the ignition key is OFF.
- DTC B12AE Passenger Heated Seat Relay Drive Circuit Open or Shorted to Ground - If the passenger heated seat relay drive circuit CHS07 (GY/BU) is open or shorted to ground and the HVAC module attempts to activate the passenger heated seat relay, the DTC will set and the seat will fail to heat (circuit open) or may be on at all times (circuit shorted to ground) until the ignition key is OFF.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Heated seat relay
- Backrest or cushion heater mat
- HVAC module

D1:

D2: