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Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
      CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
  2. CHECK FOR OPEN IN CAN BUS WIRE (MAIN BODY ECU BRANCH WIRE) 
    1. Disconnect the H2 main body ECU connector.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Switch Condition Specified Condition
      H2-5 (CANH) - H2-6 (CANL) Ignition switch off 54 to 69 Ω

    NG: REPAIR OR REPLACE MAIN BODY ECU BRANCH WIRE OR CONNECTOR (CANH, CANL) 

    Fig 1: Identifying H2 Main Body ECU Connector Terminals
    G05653038Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND) 
    1. Reconnect the cable to the negative (-) battery terminal.
    2. Disconnect the DA, DB and DD main body ECU connectors.
    3. Measure the resistance according to the value (s) in the table below.
      Fig 2: Identifying DA, DB And DD Main Body ECU Connector Terminals
      G05163432Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Condition Specified Condition
      DD-62 (GND1) - Body ground Always Below 1 Ω
    4. Measure the voltage according to the value (s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Condition Specified Condition
      DA-1 (ALTB) - Body ground Always 11 to 14 V
      DB-13 (BECU) - Body ground

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU 

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