Diagnostic 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.

NOTE: If not using the hand-held tester, start the inspection from step 2.

Connect the hand-held tester to the DLC3 and turn the ignition and hand-held tester switch ON. See Figure. Check that the wireless door lock buzzer can be operated in an ACTIVE TEST. If the wireless door lock buzzer sounds, the circuit is OK. Further diagnosis is needed. If the wireless door lock buzzer doesn't sound, go to the next step.
Check the wireless door lock buzzer. See WIRELESS DOOR LOCK BUZZER under COMPONENT TESTS under REMOTE KEYLESS ENTRY article under DOOR LOCKS & ANTI-THEFT SYSTEMS in ACCESSORIES & EQUIPMENT. If the results are OK, go to the next step. If the results are not OK, replace the wireless door lock buzzer.
Check the wiring harness and connector between the wireless door lock buzzer 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.