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Inspection Procedure

NOTE: When replacing the brake actuator assembly, perform zero point calibration (See CALIBRATION  ).
  1. INSPECT STOP FUSE 
    1. Remove the STOP fuse from the instrument panel J/B.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      STOP fuse Always Below 1 Ω
    3. Install the STOP fuse.
      4. Fig 1: Identifying STOP Fuse Of Instrument Panel J/B
      G05841903Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP FUSE 

    OK: Go to next step 

  2. CHECK STOP LIGHT (OPERATION) 
    1. Check that the stop light comes on when the brake pedal is depressed, and goes off when the brake pedal is released.

      OK 

      VOLTAGE SPECIFICATION

      Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

    NG:  Go to step  10

    OK: Go to next step 

  3. INSPECT SKID CONTROL ECU (STP1 TERMINAL) 
    1. Disconnect the skid control ECU connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      S1-27 (STP1) - Body ground Stop light switch ON (Brake pedal depressed) 8 to 14 V
      S1-27 (STP1) - Body ground Stop light switch OFF (Brake pedal released) Below 1.5 V
      3. Fig 2: Identifying Skid Control ECU (STP1 Terminal)
      G05841904Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STP1 CIRCUIT) 

    OK: Go to next step 

  4. INSPECT SKID CONTROL ECU (IG1 VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      S1-46 (IG1) - Body ground Ignition switch ON 10 to 14 V
      3. Fig 3: Identifying Skid Control ECU Connector Terminal
      G05841905Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT) 

    OK: Go to next step 

  5. INSPECT SKID CONTROL ECU (GND TERMINALS) 
    1. Turn the ignition switch off.
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      S1-32 (GND1) - Body ground Always Below 1 Ω
      S1-1 (GND2) - Body ground Always Below 1 Ω
      3. Fig 4: Identifying Skid Control ECU (GND Terminals)
      G05841906Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to next step 

  6. READ VALUE OF INTELLIGENT TESTER (STOP LIGHT SWITCH SIGNAL) 
    1. Reconnect the skid control ECU connector.
    2. Connect the intelligent tester to the DLC3.
    3. Start the engine.
    4. Select the Data List mode on the intelligent tester (See DATA LIST / ACTIVE TEST  ).

      ABS/VSC: 

      NORMAL CONDITION CHART

      Tester Display Measurement Item/Range Normal Condition
      STOP LIGHT SW Stop light switch / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released
      STEP FORCE SW Brake pedal load sensing switch / ON or OFF ON: Brake pedal depressed beyond the specified point
      OFF: Brake pedal not depressed beyond the specified point
    5. Check that the stop light display observed on the intelligent tester changes when the brake pedal is depressed.

      OK: 

      When the brake pedal is depressed, the intelligent tester displays "ON". 

    6. Slowly depress the brake pedal, and check when the stop light switch and brake pedal load sensing switch turn ON.

      OK: 

      First the stop light switch should turn ON, and then the brake pedal load sensing switch should turn ON. 

      Result 

      DTC RESULT REFERENCE

      Result Proceed to
      OK A
      NG (The turning on of the stop light switch is not confirmed) B
      NG (The turning on of the brake pedal load sensing switch is confirmed faster than the stop light switch) C

    B: REPLACE BRAKE ACTUATOR ASSEMBLY (See  REMOVAL   ) 

    C:  Go to step  8

    A: Go to next step 

  7. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR  ).
    2. Start the engine.
    3. Depress the brake pedal several times to test the stop light circuit.
    4. Check if the same DTC is recorded (See DTC CHECK / CLEAR  ).

      Result 

      DTC RESULT REFERENCE

      Result Proceed to
      DTC (C1249/49) is not output A
      DTC (C1249/49) is output B

      HINT:

      If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (See PROBLEM SYMPTOMS TABLE  ).

    B: REPLACE BRAKE ACTUATOR ASSEMBLY (See  REMOVAL   ) 

    A: CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (See  DIAGNOSIS SYSTEM   ) 

  8. CHECK BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION 
    1. Check the brake pedal height and stop light switch installation (See ADJUSTMENT ).

      OK: 

      The brake pedal and stop light switch are normal. 

    NG: ADJUST BRAKE PEDAL AND STOP LIGHT SWITCH INSTALLATION  (See ADJUSTMENT )

    OK: Go to next step 

  9. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR  ).
    2. Start the engine.
    3. Depress the brake pedal several times to test the stop light circuit.
    4. Check if the same DTC is recorded (See DTC CHECK / CLEAR  ).

      Result 

      DTC RESULT REFERENCE

      Result Proceed to
      DTC (C1249/49) is not output A
      DTC (C1249/49) is output B

      HINT:

      If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (See PROBLEM SYMPTOMS TABLE  ).

    B: REPLACE BRAKE PEDAL SUB-ASSEMBLY (BRAKE PEDAL LOAD SENSING SWITCH)  (See REMOVAL )

    A: CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (See  DIAGNOSIS SYSTEM   ) 

  10. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL) 
    1. Disconnect the stop light switch connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      S13-2 - Body ground Always 10 to 14 V
      3. Fig 5: Identifying Stop Light Switch Connector Terminal
      G05841907Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

    OK: Go to next step 

  11. INSPECT STOP LIGHT SWITCH 
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE REFERENCE

      Tester Connection Switch Condition Specified Condition
      1 - 2 Switch pin free Below 1 Ω
      1 - 2 Switch pin pushed in 10 kΩ or higher
      Fig 6: Inspecting Stop Light Switch
      G05841908Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      DTC RESULT REFERENCE

      Result Proceed to
      OK (with dynamic laser cruise control) A
      OK (without dynamic laser cruise control) B
      NG C

    B:  Go to step  16

    C: REPLACE STOP LIGHT SWITCH 

    A: Go to next step 

  12. INSPECT BRK RELAY 
    1. Remove the BRK relay.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      3 - 4 Always Below 1 Ω
      3. Fig 7: Identifying BRK Relay
      G05841909Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE BRK RELAY 

    OK: Go to next step 

  13. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - R/B NO. 3) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      S13-1 - BRK relay terminal 4 Always Below 1 Ω
      S13-1 - Body ground Always 10 kΩ or higher
      2. Fig 8: Identifying Harness And Connector (Stop Light Switch - R/B No. 3)
      G05841910Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH - R/B NO. 3) 

    OK: Go to next step 

  14. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - R/B NO. 3) 
    1. Disconnect the skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      S1-27 (STP1) - BRK relay terminal 3 Always Below 1 Ω
      S1-27 (STP1) - Body ground Always 10 kΩ or higher
      3. Fig 9: Identifying Harness And Connector (Skid Control ECU - R/B No. 3)
      G05841911Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - R/B NO. 3) 

    OK: Go to next step 

  15. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR  ).
    2. Start the engine.
    3. Depress the brake pedal several times to test the stop light circuit.
    4. Check if the same DTC is recorded (See DTC CHECK / CLEAR  ).

      HINT:

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

      Result 

      DTC RESULT REFERENCE

      Result Proceed to
      DTC (C1249/49) is not output A
      DTC (C1249/49) is output B

      HINT:

      If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (See PROBLEM SYMPTOMS TABLE  ).

    B: REPLACE BRAKE ACTUATOR ASSEMBLY (See  REMOVAL   ) 

    A: INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT)  (See LIGHTING SYSTEM )

  16. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - SKID CONTROL ECU) 
    1. Disconnect the skid control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE REFERENCE

      Tester Connection Specified Condition
      S1-27 (STP1) - S13-1 (STP) Below 1 Ω
      S1-27 (STP1) - Body ground 10 kΩ or higher
      3. Fig 10: Identifying Harness And Connector (Stop Light Switch - Skid Control ECU)
      G05841912Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH - SKID CONTROL ECU) 

    OK: Go to next step 

  17. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR  ).
    2. Start the engine.
    3. Depress the brake pedal several times to test the stop light circuit.
    4. Check if the same DTC is recorded (See DTC CHECK / CLEAR  ).

      HINT:

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

      Result 

      DTC RESULT REFERENCE

      Result Proceed to
      DTC (C1249/49) is not output A
      DTC(C1249/49) is output B

      HINT:

      If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (See PROBLEM SYMPTOMS TABLE  ).

    B: REPLACE BRAKE ACTUATOR ASSEMBLY (See  REMOVAL   ) 

    A: INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT)  (See LIGHTING SYSTEM )

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