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DTC C1425: Open in Stop Switch Circuit [11/2017 - 03/2019]: Procedure

  1. CHECK STOP LIGHT OPERATION 
    1. Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.

      OK

      Condition Illumination Condition
      Brake pedal depressed. On
      Brake pedal released. Off

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH ASSEMBLY) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Select the Data List using the Techstream.

      Refer to DATA LIST / ACTIVE TEST [11/2017 - 03/2019]

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Stop Light SW Stop light switch assembly ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released      		 -

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display
      Stop Light SW
    4. Check that the stop light switch assembly condition observed on the Techstream changes according to brake pedal operation.

      OK

      The Techstream displays ON or OFF according to brake pedal operation.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  4

    Result: 

    OK 

    See step  3

  3. RECONFIRM DTC 
    1. Turn the engine switch off.
    2. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [11/2017 - 03/2019]

      Chassis > ABS/VSC/TRAC > Clear DTCs 

    3. Turn the engine switch off.
    4. Start the engine.
    5. Depress the brake pedal several times to test the stop light circuit.
    6. Check if the same DTC is output.

      Refer to DTC CHECK / CLEAR [11/2017 - 03/2019]

      Chassis > ABS/VSC/TRAC > Trouble Codes 

      Result

      Result Proceed to
      DTC C1425 is not output. A
      DTC C1425 is output. B

      HINT: 

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.

      Refer to PROBLEM SYMPTOMS TABLE [11/2017 - 03/2019]

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 03/2019] 

    Result: 

    B 

    REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2017 - 01/2023] 

  4. CHECK HARNESS AND CONNECTOR (STP TERMINAL) 
    1. Turn the engine switch off.
      GTY800273Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control ECU (Brake Actuator Assembly))
    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    3. Disconnect the A86 skid control ECU (brake actuator assembly) connector.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A86-35 (STP) - Body ground Stop light switch assembly on (Brake pedal depressed) 8 to 14 V
      A86-35 (STP) - Body ground Stop light switch assembly off (Brake pedal released) Below 1.5 V

      HINT: 

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.

      Refer to PROBLEM SYMPTOMS TABLE [11/2017 - 03/2019]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [11/2017 - 01/2023] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 

  5. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Check the stop light switch assembly.

      Refer to ON-VEHICLE INSPECTION [09/2014 - ]

      OK

      The stop light switch assembly is normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (STP TERMINAL) 
    1. Turn the engine switch off.
      GTY800273Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control ECU (Brake Actuator Assembly))
    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    3. Disconnect the A86 skid control ECU (brake actuator assembly) connector.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A86-35 (STP) - Body ground Stop light switch assembly on (Brake pedal depressed) 8 to 14 V
      A86-35 (STP) - Body ground Stop light switch assembly off (Brake pedal released) Below 1.5 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (STP TERMINAL) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
      GTY781041Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Semiconductor PWR Integration ECU)
    2. Disconnect the 2D semiconductor PWR integration ECU connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2D-10 (STP) - Body ground Stop light switch assembly on (Brake pedal depressed) 8 to 14 V
      2D-10 (STP) - Body ground Stop light switch assembly off (Brake pedal released) Below 1.5 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) 

    Result: 

    OK 

    See step  8

  8. RECONFIRM DTC 
    1. Reconnect the A86 skid control ECU (brake actuator assembly) connector.
    2. Reconnect the 2D semiconductor PWR integration ECU connector.
    3. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [11/2017 - 03/2019]

      Chassis > ABS/VSC/TRAC > Clear DTCs 

    4. Turn the engine switch off.
    5. Start the engine.
    6. Depress the brake pedal several times to test the stop light circuit.
    7. Check if the same DTC is output.

      Refer to DTC CHECK / CLEAR [11/2017 - 03/2019]

      Chassis > ABS/VSC/TRAC > Trouble Codes 

      Result

      Result Proceed to
      DTC C1425 is not output. A
      DTC C1425 is output. B

      HINT: 

      • If the lighting system is normal but the DTC is still output, replace the skid control ECU (brake actuator assembly).

        Refer to REMOVAL [11/2017 - 01/2023]

      • If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.

        Refer to PROBLEM SYMPTOMS TABLE [11/2017 - 03/2019]

    Result: 

    A 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 03/2019] 

    Result: 

    B 

    INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) 

    for Single Beam Headlight: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 03/2019]

    for Triple Beam Headlight: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 03/2019]

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