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Inspection Procedure

  1. CHECK FUSE (AM1, MPX-IG, MPX-B3) 
    1. Remove the AM1 fuse and MPX-IG fuse from the driver side J/B.
    2. Remove the MPX-B3 fuse from the passenger side J/B.
    3. Measure the resistance of the fuse.
      1. Standard: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step 

  2. CHECK WIRE HARNESS (DRIVER SIDE J/B AND DRIVER SIDE J/B ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the DA, DE, DF and DG J/B connectors.
    2. Disconnect the D5 ECU connector.
    3. Measure the voltage and resistance of the wire harness side connectors.
      Fig 1: Driver Side J/B And Driver Side J/B ECU Connector
      G03001917Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TESTER CONNECTION CONDITION CHART

      Tester Connection Condition Specified Condition
      DA-1 (MPX-IG) - Body ground Always 10 to 14V
      D5-5 (MPX-B) - Body ground Always 10 to 14V
      DG-8 (GND) - Body ground Always Below 1 Ω
      D5-1 (GND2) - Body ground Always Below 1 Ω
      DE-17 (MPX-IG) -DF-4 (GND) Ignition switch OFF --> ON 10 kΩ or higher --> Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  3. INSPECT RELAY (Marking: D-IG1) 
    1. Remove the D-IG1 relay from the driver side J/B.
    2. Measure the resistance of the relay.
      Fig 2: Identifying D-IG1 Relay Terminals
      G03001918Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TESTER CONNECTION CONDITION CHART

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

    NG: REPLACE RELAY 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE  )