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Inspection Procedure

This is the procedure for without Dynamic Laser Cruise Control System.

NOTE: When replacing the brake actuator assembly, perform zero point calibration (See CALIBRATION  ).
  1. CHECK STOP LIGHT SWITCH OPERATION 
    1. Check that the stop lights come on when the brake pedal is depressed and goes off when the brake pedal is released.

      OK: 

      PEDAL CONDITION TABLE

      Pedal Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

      HINT:

      Check the stop light bulb as it may have burnt out.

    NG: Go to step   4 

    OK: Go to next step 

  2. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (STP TERMINAL) 
    1. Disconnect the skid control ECU connector.
      Fig 1: Identifying Skid Control ECU Connector
      G05272717Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION TABLE

      Tester Connection Switch Condition Specified Condition
      S1 - 27 (STP1) - Body ground Brake pedal depressed 8 to 14 V
      S1-27 (STP1) - Body ground Brake pedal released Below 1 V

    NG: Go to step   5 

    OK: Go to Next Step 

  3. RECONFIRM DTC 
    1. Clear the DTCs (See DTC CHECK/CLEAR  ).
    2. Turn the ignition switch to the ON position.
    3. Check if the same DTCs are detected.

      Result 

      RESULT REFERENCE

      Result Proceed to
      DTC is output A
      DTC is not output B
      NOTE: When replacing the brake actuator assembly, perform zero point calibration (See CALIBRATION  ).

    B: CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)  (See TERMINALS OF ECU  )

    A: REPLACE BRAKE ACTUATOR ASSEMBLY  (See REMOVAL  )

  4. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Disconnect the stop light switch assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Switch Condition Tester Connection Specified Condition
      Switch pin free 1 - 2 Below 1 Ω
      Switch pin pushed in 1 - 2 10 kΩ or higher
      Fig 2: Identifying Stop Light Switch Assembly
      G05272721Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

    OK: Go to Next Step 

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

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Specified Condition
      S1-27 (STP1) - S13-1 (STP) Below 1 Ω
      Fig 3: Identifying Stop Light Switch & Skid Control ECU Connector
      G05272722Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: When replacing the brake actuator assembly, perform zero point calibration (See CALIBRATION  ).

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE BRAKE ACTUATOR ASSEMBLY  (See REMOVAL  )



This is the procedure for with Dynamic Laser Cruise Control System.

NOTE: When replacing the brake actuator assembly, perform zero point calibration (See CALIBRATION  ).
  1. INSPECT STOP FUSE 
    1. Remove the STOP fuse from the R/B NO. 3.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      STOP fuse Always Below 1 Ω
      Fig 1: Identifying STOP Fuse From R/B No. 3
      G05272723Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Install the STOP fuse.

    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 

      BRAKE PEDAL CONDITION TABLE

      Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

    NG: Go to step   8 

    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 

      STANDARD VOLTAGE SPECIFICATION TABLE

      Tester Connection 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
      Fig 2: Identifying Skid Control ECU Connector
      G05272717Courtesy 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 

      STANDARD VOLTAGE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S1 - 46 (IG1) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 3: Identifying Skid Control ECU Connector
      G05272725Courtesy 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 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S1 - 32 (GND1) - Body ground Always Below 1 Ω
      S1 - 1 (GND2) - Body ground Always Below 1 Ω
      Fig 4: Identifying Skid Control ECU Connector
      G05272726Courtesy 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.

      ABS /TRAC /VSC: 

      DATA LIST - ABS/TRAC/VSC

      Item (Display) Measurement Item / Range (Display) Normal Condition
      STOP LIGHT SW Stop light switch / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released
      STEP FORCE SW Stepping force switch / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released
    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 stepping force switch turn ON.

      OK: 

      First the stop light switch should turn ON, and then the stepping force switch should turn ON. 

      Result 

      RESULT REFERENCE TABLE

      Condition Proceed to
      OK A
      NG (The turning on of the stop light switch is not confirmed) B
      NG (The turning on of the stepping force 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. CONFIRM DTC (C1249/49) 
    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 

      RESULT REFERENCE

      Condition 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 TERMINALS OF ECU  )

  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 (C1249/49) 
    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 

      RESULT REFERENCE TABLE

      Condition 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: Go to step   10 

    A: CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)  (See TERMINALS OF ECU  )

  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 

      STANDARD VOLTAGE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S13-2 - Body ground Always 10 to 14 V
      Fig 5: Identifying Stop Light Switch Connector Terminal
      G05272727Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH - POWER SOURCE CIRCUIT) 

    OK: Go to Next Step 

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

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      1 - 2 Switch pin free Below 1 Ω
      1 - 2 Switch pin pushed in 10 kΩ or higher
      Fig 6: Identifying Stop Light Switch Assembly
      G05272721Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

    OK: 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 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      3 - 4 Always Below 1 Ω
      Fig 7: Identifying BRK Relay
      G05140654Courtesy 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 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S13-1 - Stop light control relay terminal 4 Always Below 1 Ω
      S13-1 - Body ground Always 10 kΩ or higher
      Fig 8: Identifying Stop Light Switch & R/B No. 3 Connector Terminal
      G05272730Courtesy 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 

      STANDARD RESISTANCE SPECIFICATION TABLE

      Tester Connection Condition Specified Condition
      S1 - 27 (TP1) - Stop light control relay terminal 3 Always Below 1 Ω
      S1 - 27 (STP1) - Body ground Always 10 kΩ or higher
      Fig 9: Identifying Skid Control ECU & R/B No. 3 Connector Terminal
      G05272731Courtesy 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 (C1249/49) 
    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 

      RESULT REFERENCE TABLE

      Condition 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) 

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