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Inspection Procedure

WARNING: This page is about a different car, the 2007 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT FUSE (ACC, ECU-B2, ECU-IG1) 
    1. Remove the ACC, ECU-IG1 fuses from the cowl side junction block LH.
    2. Remove the ECU-B2 fuse from the cowl side junction block RH.
    3. Measure the resistance of the fuses.

      Standard resistance: 

      Below 1 Ω 

    • NG: REPLACE FUSE 
    • OK: GO TO NEXT STEP 
  2. CHECK WIRE HARNESS (NETWORK GATEWAY ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the G4 ECU connector.
    2. Measure the resistance of the wire harness side connector.

      Standard resistance 

      NETWORK GATEWAY ECU - BATTERY AND BODY GROUND (RESISTANCE)

      Tester Connection Specified Condition
      G4-24 (GND) - Body ground Below 1 Ω
    3. Measure the voltage of the wire harness side connector.

      Standard voltage 

      NETWORK GATEWAY ECU - BATTERY AND BODY GROUND (VOLTAGE)

      Tester Connection Condition Specified Condition
      G4-10 (BATT) - G4-24 (GND) Always 10 to 14 V
      G4-2 (ACC) - G4-24 (GND) Ignition switch ACC 10 to 14 V
      G4-1 (IG) - G4-24 (GND) Ignition switch ON 10 to 14 V
      Fig 1: Checking Wire Harness (Network Gateway ECU - Battery And Body Ground)
      G04438717Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
    • OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE