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Inspection Procedure

  1. CHECK FREEZE FRAME DATA 
    1. Check the information code from the "FREEZE FRAME DATA" memorized when the DTC (C1377/43) is stored (see FREEZE FRAME DATA  ).

      Result 

      RESULT REFERENCE

      Result Proceed to
      Information codes (109 and 110) are output A
      Information codes (101, 102, 105, 106 and 108) are output B
      Information code (103) is output C

    B: REPLACE BRAKE CONTROL POWER SUPPLY (See  REMOVAL   ) 

    C: Go to step   6 

    A: GO TO NEXT STEP 

  2. INSPECT FUSE (ABS MAIN4) 
    1. Remove the ABS MAIN4 fuse from the luggage room relay block (junction block).
    2. Measure the resistance of the fuse.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      ABS MAIN4 fuse Always Below 1 Ω

    NG: REPLACE FUSE 

    OK: GO TO NEXT STEP 

  3. INSPECT BRAKE CONTROL POWER SUPPLY (+BC AND GND TERMINAL) 
      Fig 1: Identifying S49 Power Supply Connector
      G04949665Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S49 power supply connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      S49-8 (+BC) - Body ground Always 11 to 14 V
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      S49-14 (GND) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (+BC OR GND CIRCUIT) 

    OK: GO TO NEXT STEP 

  4. INSPECT BRAKE CONTROL POWER SUPPLY (CTY+ AND OUT TERMINAL) 
      Fig 2: Identifying S49 Power Supply Connector
      G04949666Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the voltage according to the value (s) in the table below.

      HINT:

      Perform inspection while the brake is not operated.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      S49-1 (OUTI)-Body ground Always 11 to 14 V
      S49-7 (OUT2) - Body ground Always 11 to 14 V

    OK: Go to step   8 

    NG: GO TO NEXT STEP 

  5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BRAKE CONTROL POWER SUPPLY) 
      Fig 3: Identifying A19, A21 ECU Connectors And S49 Power Supply Connector
      G04949667Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A19 and A21 ECU connectors.
    2. Disconnect the S49 power supply connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A19-38 (CBI1) - S49-1 (OUT1) V Always Below 1 Ω
      A21-40 (CBI2) - S49-7 (OUT2) Always Below 1 Ω
      A19-38 (CBI1)-Body ground Always 10 kΩ or higher
      A21-40 (CBI2)-Body ground Always 10 kΩ or higher

    OK: Go to step   8 

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

  6. INSPECT BATTERY 
    1. Check the battery voltage.

      Standard voltage: 11 to 14 V 

    NG: INSPECT CHARGING SYSTEM  (See ON-VEHICLE INSPECTION )

    OK: GO TO NEXT STEP 

  7. INSPECT BRAKE CONTROL POWER SUPPLY (+BC TERMINAL) 
      Fig 4: Identifying S49 Power Supply Connector
      G04949668Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S49 power supply connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      S49-8 (+BC) - Body ground Always 11 to 14V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (+BC CIRCUIT) 

    OK: GO TO NEXT STEP 

  8. RECONFIRM DTC 
    1. Clear the DTC (see DTC CHECK/CLEAR  ).
    2. Turn the engine switch on (IG).
    3. Check if the same DTC is recorded (see DTC CHECK/CLEAR  ).

      HINT:

      Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

      Result 

      RESULT REFERENCE

      Result Proceed to
      DTC (C1377/43) is not output A
      DTC (C1377/43) is output B

    B: REPLACE BRAKE CONTROL POWER SUPPLY (See  REMOVAL   ) 

    A: GO TO NEXT STEP 

    END 

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