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Problem Symptoms Table

HINT:

Use PROBLEM SYMPTOMS TABLE  to help determine the cause of the problem symptom. The potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

PROBLEM SYMPTOMS TABLE

Symptom Suspected Area Reference
Both front seat heaters do not warm up
  • IG1 relay
  • P-IG fuse
  • SEAT HTR fuse
  • Front seat heater switch
  • Wire harness
INSPECTION 
Front seat cushion heater LH does not warm up
  • Front seat heater switch
  • Seat heater control sub-assy LH
  • Wire harness
  • Front seat cushion heater LH
INSPECTION 
Front seatback heater LH does not warm up
  • Front seat heater switch
  • Seat heater control sub-assy LH
  • Wire harness
  • Front seatback heater LH
INSPECTION 
Front seat cushion heater RH does not warm up
  • Front seat heater switch
  • Seat heater control sub-assy RH
  • Wire harness
  • Front seat cushion heater RH
INSPECTION 
Front seatback heater RH does not warm up
  • Front seat heater switch
  • Seat heater control sub-assy RH
  • Wire harness
  • Front seatback heater RH
INSPECTION 

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 MULTIPLEX COMMUNICATION SYSTEM - DIAGNOSTICS ).