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Problem Symptoms Table

PROBLEM SYMPTOMS

Symptom Suspected Area See
All front seat heaters do not warm up
  1. P-IG1 relay
  2. P-IG fuse
  3. Front seat heater switch
  4. Wire harness
INSPECTION 
INSPECTION 
INSPECTION 
INSPECTION 
Front LH seat cushion heater does not warm up
  1. D S/HTR fuse
  2. D-IG1 relay
  3. Front seat heater switch
  4. Wire harness
  5. Front seat cushion heater LH
INSPECTION 
INSPECTION 
INSPECTION 
INSPECTION 
(1)
Front LH seatback heater does not warm up
  1. D S/HTR fuse
  2. D-IG1 relay
  3. Front seat heater switch
  4. Wire harness
  5. Front seat cushion heater LH
  6. Front seatback heater LH
INSPECTION 
INSPECTION 
INSPECTION 
INSPECTION 
(1)
(1)
Front RH seat cushion heater does not warm up
  1. P S/HTR fuse
  2. Front seat heater switch
  3. Wire harness
  4. Front seat cushion heater RH
INSPECTION 
INSPECTION 
INSPECTION 
(1)
Front RH seatback heater does not warm up
  1. P S/HTR fuse
  2. Front seat heater switch
  3. Wire harness
  4. Front seat cushion heater RH
  5. Front seatback heater RH
INSPECTION 
INSPECTION 
INSPECTION 
(1)
(1)
All rear seat heaters do not warm up
  1. RR S/HTRfuse
  2. L-IG1 relay
  3. Rear seat heater switch
  4. Wire harness
INSPECTION 
INSPECTION 
INSPECTION 
INSPECTION 
Rear LH seat cushion heater does not warm up
  1. Rear seat heater switch
  2. Wire harness
  3. Rear seat cushion heater LH
INSPECTION 
INSPECTION 
(1)
Rear LH seatback heater does not warm up
  1. Rear heater switch
  2. Wire harness
  3. Rear seat cushion heater LH
  4. Rear seatback heater LH
INSPECTION 
INSPECTION 
(1)
(1)
Rear RH seat cushion heater does not warm up
  1. Rear seat heater switch
  2. Wire harness
  3. Rear seat cushion heater RH
INSPECTION 
INSPECTION 
(1)
Rear RH seatback heater does not warm up
  1. Rear seat heater switch
  2. Wire harness
  3. Rear seat cushion heater RH
  4. Rear seatback heater RH
INSPECTION 
INSPECTION 
(1)
(1)
Temperature of front seat heater cannot be adjusted (seat does not warm up)
  1. Front seat heater switch
  2. Wire harness
INSPECTION 
 
INSPECTION 
Temperature of rear seat heater cannot be adjusted (seat does not warm up)
  1. Rear seat heater switch
  2. Wire harness
INSPECTION 
INSPECTION 
NOTE:
(1) The seat heater can only be inspected through other items listed in the suspected area of the (see PROBLEM SYMPTOMS TABLE ). If normal operations of these items are confirmed, the seat heater may be malfunctioning.

HINT:

The seat heater system is part of the large-scale multiplex communication system. This system features shared communication wiring that reduces the wiring complexity of the communication lines. The first step in any repair is to confirm the proper operation of the communication system. Proceed with troubleshooting after the communication has been verified (see the multiplex communication system).