Rear Seat Heater Indicator Does Not Illuminate

Wiring diagram: 

Seat heater system Ref. to WIRING SYSTEM>SEAT HEATER SYSTEM>WIRING DIAGRAM

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK SEAT HEATER SWITCH UNIT (INDICATOR)  .
   1. Turn the ignition switch to OFF.
   2. Remove the seat heater switch. Ref. to SEATS>SEAT HEATER>REMOVAL>REAR SEAT HEATER SWITCH 
   3. Apply battery voltage between seat heater switch terminals, and perform the inspection.
   4. Operate the LH side and RH side switches to HI and LO. Ref. to SEATS>SEAT HEATER>INSPECTION>SEAT HEATER SWITCH 

   Does the indicator illuminate when the switch is operated to HI/LO?

   Yes  : Go to  2.

   No  : Replace the seat heater switch.

2. CHECK HARNESS  .

   Measure the resistance between rear seat heater control module and seat heater switch harness connector terminal.

   Connector & terminal 

   LH side 

   (R84) No. 14 - (R58) No. 1:

   (R84) No. 16 - (R58) No. 6:

   (C3) No. 1 - (C34) No. 2:

   (C3) No. 6 - (C34) No. 3:

   (C34) No. 8 - Chassis ground:

   RH side 

   (R84) No. 4 - (R58) No. 5:

   (R84) No. 2 - (R58) No. 3:

   (C3) No. 5 - (C33) No. 1:

   (C3) No. 3 - (C33) No. 2:

   (C33) No. 6 - Chassis ground:

   Is the resistance less than 10 Ω?

   Yes  : Replace the rear seat heater control module.

   No  : Repair or replace the defective part.