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Inspection Procedure

  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 prevent airbag and seat belt pretensioner activation.
      NOTE:
      • After the engine switch is turned off, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the engine switch off, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.
      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected (see INITIALIZATION ).
  2. CHECK FOR OPEN IN CAN BUS WIRE (SKID CONTROL ECU BRANCH WIRE) 
      Fig 1: Identifying Terminals Of A19 And A21 Skid Control ECU Connectors
      G04953394Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A19 and A21 skid control ECU connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      A21-30 (CA1H) - A21-29 (CA1L) Engine switch off 54 to 69 Ω
      A19-7 (CA2H) - A19-6 (CA2L) Engine switch off 54 to 69 Ω

    NG: REPAIR OR REPLACE SKID CONTROL ECU BRANCH WIRE OR CONNECTOR (CA1H, CA1L, CA2H, CA2L) 

    OK: GO TO NEXT STEP 

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BATTERY AND BODY GROUND) 
    1. Connect the cable to the negative (-) battery terminal.
      NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (see INITIALIZATION ).
    2. Disconnect the A19 and A21 skid control ECU connectors.
      Fig 2: Identifying Terminals Of A19 And A21 Skid Control ECU Connectors
      G04953395Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A19-1 (GND) - Body ground Always Below 1 Ω
      A21-1 (GND4) - 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 CHART

      Tester Connection Switch Condition Specified Condition
      A19-43 (+BI1) - Body ground Always 11 to 14 V
      A21-38 (+BI2) - Body ground Always 11 to 14 V
      A19-29 (+BI3) - Body ground Always 11 to 14 V
      A21-22 (+BI4) - Body ground Always 11 to 14 V
      A19-46 (IG1) - Body ground Engine switch on (IG) 11 to 14 V
      A21-46 (IG2) - Body ground Engine switch on (IG) 11 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE SKID CONTROL ECU  (See REMOVAL )

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