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Power Source Control ECU Communication Stop Mode: Procedure

  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistance of the CAN main wire or CAN branch wire.
      WARNING:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      NOTE:

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

    NEXT: Go to next step 

  2. CHECK FOR OPEN IN CAN BUS WIRE (POWER SOURCE CONTROL ECU CAN BRANCH WIRE) 
    1. Disconnect the C43 power source control ECU connector.
      Fig 1: Checking CAN Bus Wire (Power Source Control ECU)
      GTY313853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      C43-14 (CA1H) - C43-13 (CA1L) Ignition switch off 54 to 69 Ω
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Source Control ECU)

    NG → REPAIR OR REPLACE POWER SOURCE CONTROL ECU CAN BRANCH WIRE OR CONNECTOR (CA1H, CA1L) 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND) 
    1. Connect the cable to the negative (-) battery terminal.
      Fig 2: Checking Power Source Control ECU - Battery And Body Ground
      GTY311730Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE:

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION .

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      C43-5 (GND2) - Body ground Always Below 1 Ω
      C43-6 (GND) - Body ground Always Below 1 Ω
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      C43-1 (AM22) - Body ground Always 11 to 14 V
      C43-2 (AM21) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Power Source Control ECU)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   4 

  4. REPLACE POWER SOURCE CONTROL ECU. Refer to  REMOVAL 
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