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Front Passenger Side Door ECU Power Source Circuit: Procedure

  1. INSPECT FUSE (AM1, MPX-B1, MPX-IG, P-DOOR, D/C CUT) 
    1. Remove the AM1 and MPX-IG fuses from the driver side junction block.
    2. Remove the MPX-B1 fuse from the passenger side junction block.
    3. Remove the P-DOOR and D/C CUT fuses from the engine room No. 1 relay block.
    4. Measure the resistance of the fuses.

      Standard resistance

      Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  2. INSPECT RELAY (Marking: IG1) 
    1. Remove the IG1 relay from the driver side junction block.
      Fig 1: Identifying IG1 Relay Connector Terminals
      GTY127255Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance of the relay.

      Standard resistance

      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: Go to next step 

  3. CHECK WIRE HARNESS (DOOR ECU FRONT RH - BATTERY AND BODY GROUND) 
    1. Disconnect the P11 ECU connector.
      Fig 2: Identifying P11 ECU Connector Terminals
      GTY120222Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance and voltage of the wire harness side connector.

      Standard resistance

      Standard voltage 

      Tester Connection Condition Specified Condition
      P11-1 (GND) - Body ground Always Below 1 Ω
      Tester Connection Condition Specified Condition
      P11-4 (CPUB) - Body ground Always 10 to 14 V
      P11-6 (BDR) - Body ground Always 10 to 14 V
      P11-5 (SIG) - Body ground Ignition switch ON 10 to 14 V

    NG → REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK → REPLACE MULTIPLEX NETWORK DOOR ECU FRONT RH