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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

      Condition Proceed To
      Information codes (109, and 110) are output A
      Information codes (101,102,105,106,107, and 108) are output B
      Information code (103) is output C

    B : REPLACE BRAKE CONTROL POWER SUPPLY 

    C :  Go to step  7

    A : Go to Next Step 

  2. INSPECT FUSE (ABS1 AND ABS MAIN1 FUSES) 
    1. Remove the ABS1 and ABS MAIN1 fuses from the engine room R/B (J/B) No.1.
    2. Check the ABS1 and ABS MAIN1 fuses.

      Resistance: 

      Below 1 Ω (Continuity) 

    NG : REPLACE FUSE (ABS1 OR ABS MAIN1 FUSE) 

    OK : Go to Next Step 

  3. INSPECT BRAKE CONTROL POWER SUPPLY (+BC AND GND TERMINAL) 
    1. Disconnect the brake control power supply connector.
    2. Measure the voltage according to the value (s) in the table below.

      Voltage 

      VOLTAGE REFERENCE CHART

      Tester Connection Specified Condition
      U27-8 (+BC) - Body ground 10 to 14 V
    3. Measure the resistance according to the value (s) in the table below.

      Resistance 

      RESISTANCE REFERENCE CHART

      Tester Connection Specified Condition
      U27-14 (GND) - Body ground Below 1 Ω
      Fig 1: Inspecting Brake Control Power Supply (+BC And GND Terminal)
      G05297100Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK : Go to Next Step 

  4. INSPECT SKID CONTROL ECU (Dl TERMINAL) 
    1. Disconnect the skid control ECU (A13, A15) connectors.
    2. Measure the voltage according to the value (s) in the table below.

      Voltage 

      VOLTAGE REFERENCE CHART

      Tester Connection Specified Condition
      A13-39 (DM) - Body ground 10 to 14 V
      A15-38 (DI2) - Body ground 10 to 14 V

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR (Dl CIRCUIT) 

    Fig 2: Inspecting Skid Control ECU (DL Terminal)
    G05807203Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to Next Step 

  5. INSPECT BRAKE CONTROL POWER SUPPLY (OUT TERMINAL) 
    1. Measure the voltage according to the value (s) in the table below.

      HINT:

      Perform inspection while the brake is not operated.

      Voltage 

      VOLTAGE REFERENCE CHART

      Tester Connection Specified Condition
      U27-1 (OUT1) - Body ground 10 to 14 V
      U27-2 (CTY+) - Body ground 10 to 14 V (1)
      U27-7 (OUT2) - Body ground 10 to 14 V
      (1) For 5 seconds after the driver's door is opened.

    OK :  Go to step  9

    Fig 3: Inspecting Brake Control Power Supply (Out Terminal)
    G05297102Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : Go to Next Step 

  6. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU TO BRAKE CONTROL POWER SUPPLY) 
    1. Disconnect the skid control ECU (A13, A15) connectors and brake control power supply connector.
    2. Measure the resistance according to the value (s) in the table below.

      Resistance 

      RESISTANCE REFERENCE CHART

      Tester Connection Specified Condition
      A13-13 (CTY+) - U27-2 (CTY+) Below 1 Ω
      A13-21 (CBI1) - U27-1 (OUT1) Below 1 Ω
      A15-40 (CBI2) - U27-7 (OUT2) Below 1 Ω
    3. Measure the resistance according to the value (s) in the table below.

      Resistance 

      RESISTANCE REFERENCE CHART

      Tester Connection Specified Condition
      A13-13 (CTY+) - Body ground 10 kΩ or higher
      A13-21 (CBI1) - Body ground 10 kΩ or higher
      A15-40 (CBI2) - Body ground 10 kΩ or higher

    OK :  Go to step  9

    Fig 4: Checking Harness And Connector (Skid Control ECU To Brake Control Power Supply)
    G05807205Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

  7. INSPECT BATTERY 
    1. Check the battery voltage.

      Voltage: 

      11 to 14 V 

    NG : INSPECT CHARGING SYSTEM 

    OK : Go to Next Step 

  8. INSPECT BRAKE CONTROL POWER SUPPLY (+BC TERMINAL) 
    1. Disconnect the brake control power supply connector.
    2. Measure the voltage according to the value (s) in the table below.

      Voltage 

      VOLTAGE REFERENCE CHART

      Tester Connection Specified Condition
      U27-8 (+BC) - Body ground 10 to 14 V

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

    Fig 5: Inspecting Brake Control Power Supply (+BC Terminal)
    G05297104Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to Next Step 

  9. 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

      Display (DTC Output) Proceed To
      DTC (C1377/43) Is not output A
      DTC (C1377/43) Is output B

    B : REPLACE BRAKE CONTROL POWER SUPPLY 

    A : END 

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