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Home >> Lexus >> 2003 >> IS 300 Base, Standard >> Repair and Diagnosis >> Body & Frame >> Windows >> Troubleshooting (Body Electrical) >> Problem Symptoms Table >> Defogger System
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Defogger System

This system uses the multiplex communication system, so check diagnosis system of the multiplex communication system before you proceed with troubleshooting.

PROBLEM SYMPTOMS - DEFOGGER SYSTEM

Symptom Suspect Area Go To
Rear window defogger does not operate.
  1. HTR Fuse
  2. DEF M-Fuse
  3. Defogger Relay Circuit
  4. Defogger Switch (in A/C Panel Switch)
  5. Defogger Wire
  6. Wire Harness
  7. Body ECU
  8. Noise Filter
  9. A/C ECU
  1. LOCATION
  2. LOCATION
  3. DEFOGGERS
  4. AIR CONDITIONING SYSTEM (DIAGNOSIS)
  5. INSPECTION
  6. INSPECTION
  7. -
  8. BODY CONTROL SYSTEM
  9. AIR CONDITIONING SYSTEM (DIAGNOSIS)
Mirror heater does not operate.
  1. MIR-HTR Fuse (Passenger Side J/B)
  2. Mirror Heater Relay
  3. Mirror Heater
  4. Wire Harness
  1. LOCATION
  2. INSPECTION
  3. INSPECTION
  4. -
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