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Home >> Toyota >> 2004 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 224 (Anti-Theft System) >> Circuit Tests >> Key Unlock Warning Switch 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. Disconnect the key unlock warning switch connector. Check the continuity between terminal 1 and 2 of the key unlock warning switch connector, when the key is inserted into the key cylinder or removed. See CONNECTOR IDENTIFICATION . See INSPECTING KEY UNLOCK WARNING SWITCH CONTINUITY  table. If the results are OK, go to the next step. If the results are not good, replace the key unlock warning switch.
    INSPECTING KEY UNLOCK WARNING SWITCH CONTINUITY

    Switch Position Tester Connection Specified Condition
    ON (Key Inserted) 1 - 2 Continuity
    OFF (Key Removed) - No Continuity
  2. Check the harness and connectors between the theft deterrent ECU and key unlock warning switch, key unlock warning switch and body ground. If the results are OK, check and replace the theft deterrent ECU. When there is a malfunction that the anti-theft system cannot be set, proceed to the next circuit inspection of the symptom. See PROBLEM SYMPTOM INDEX  table. If the results are not good, repair or replace the harness or connector.