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Problem Symptoms Table

HINT:

The window defogger 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).

Window defogger system 

PROBLEM SYMPTOMS CHART

Symptom Suspected area Refer To
Rear window defogger does not operate (Indicator ON) 1. DEF H-fuse WINDOW DEFOGGER SYSTEM 
2. A/C (HTR) fuse WINDOW DEFOGGER SYSTEM 
3. GAUGE fuse WINDSHIELD GLASS 
4. DOME fuse WINDSHIELD GLASS 
5. ECU-B fuse WINDSHIELD GLASS 
6. DEF relay DEFOGGER RELAY 
7. Rear window defogger wire WINDOW DEFOGGER WIRE 
8. Wire harness -
Rear window defogger does not operate (Indicator OFF) 1. DEF H-fuse WINDOW DEFOGGER SYSTEM 
2. A/C (HTR) fuse WINDOW DEFOGGER SYSTEM 
3. GAUGE fuse WINDOW DEFOGGER SYSTEM 
4. DOME fuse WINDOW DEFOGGER SYSTEM 
5. ECU-B fuse WINDOW DEFOGGER SYSTEM 
6. DEF relay DEFOGGER RELAY 
7. Combination meter HOW TO PROCEED WITH TROUBLESHOOTING
8. Steering pad switch WINDOW DEFOGGER SYSTEM 
9. Multi-display assembly HOW TO PROCEED WITH TROUBLESHOOTING
10. Rear window defogger wire WINDOW DEFOGGER WIRE 
11. Wire harness -
Mirror heater does not operate (Indicator ON) 1. M/HTR fuse WINDOW DEFOGGER SYSTEM 
2. A/C (HTR) fuse WINDOW DEFOGGER SYSTEM 
3. GAUGE fuse WINDOW DEFOGGER SYSTEM 
4. DOME fuse WINDOW DEFOGGER SYSTEM 
5. ECU-B fuse WINDOW DEFOGGER SYSTEM 
6. Mirror heater relay MIRROR HEATER RELAY
7. Outer rear view mirror assembly OUTER REAR VIEW MIRROR
8. Wire harness -
Mirror heater does not operate (Indicator OFF) 1. M/HTR fuse WINDOW DEFOGGER SYSTEM 
2. A/C (HTR) fuse WINDOW DEFOGGER SYSTEM 
3. GAUGE fuse WINDOW DEFOGGER SYSTEM 
4. DOME fuse WINDOW DEFOGGER SYSTEM 
5. ECU-B fuse WINDOW DEFOGGER SYSTEM 
6. Mirror heater relay MIRROR HEATER RELAY
7. Combination meter HOW TO PROCEED WITH TROUBLESHOOTING
8. Steering pad switch WINDOW DEFOGGER SYSTEM 
9. Multi-display assembly HOW TO PROCEED WITH TROUBLESHOOTING
10. Outer rear view mirror assembly OUTER REAR VIEW MIRROR
11. Wire harness -