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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 disable the SRS system.
    NOTE:
    • w/ Navigation System:

      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) 
    1. Disconnect the A24 master cylinder solenoid (skid control ECU) connector.
    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
    A24-11 (CANH) - A24-25 (CANL) Engine switch off 54 to 69 Ω

    NG: REPAIR OR REPLACE SKID CONTROL ECU BRANCH WIRE OR CONNECTOR (CANH, CANL) 

    Fig 1: Identifying Skid Control ECU connector Terminal
    G05639437Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 A24 and A25 master cylinder solenoid (skid control ECU) connectors.
    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
      A24-1 (GND1) - Body ground Always Below 1 Ω
      A24-32 (GND2) - Body ground
      A25-4 (GND3) - Body ground
    4. Measure the voltage according to the value(s) in the table below.
    Fig 2: Checking Harness And Connector (Skid Control ECU - Battery And Body Ground)
    G05765000Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    A24-2(+BM1) - Body ground Always 11 to 14 V
    A24-31 (+BS) - Body ground
    A25-2 (+BM2) - Body ground
    A24-46(IG1) - Body ground Engine switch on (IG) 11 to 14 V
    A25-1 (IG2) - Body ground

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MASTER CYLINDER SOLENOID (SKID CONTROL ECU)  (See DISASSEMBLY )

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