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Home >> Lexus >> 2004 >> IS 300 Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 116 (Body Control System) >> Circuit Tests >> Rear Defogger Relay Circuit >> Inspection Procedure
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Inspection Procedure

WARNING: This page is about a different car, the 2003 Lexus IS 300 and 2002 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check the rear defogger relay and front defogger relay located in the driver side junction block. See DEFOGGER RELAY under COMPONENT TESTS under REAR WINDOW DEFOGGER & HEATED MIRRORS article under HEATED GLASS/DEFOGGERS in ACCESSORIES & EQUIPMENT. If the results are OK, go to the next step. If the results are not OK, replace the appropriate defogger relay.
  2. Check the wiring harness and connector between the rear defogger relay and body ECU, front defogger relay and body ECU. See WIRING DIAGRAMS . If the results are OK, the circuit is OK. Further diagnosis is needed. If the results are not OK, repair or replace the wiring harness or connector.
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