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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 main body ECU.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      STOP (10 A) fuse Always Below 1 Ω
      Fig 1: Identifying Stop Fuse
      G04978066Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP FUSE 

    OK: Go to Next Step 

  2. CHECK STOP LIGHT OPERATION 
    1. Install the STOP fuse.
    2. 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 CHART

      Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

    NG:  Go to step  7

    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

      Tester Connection Condition Specified Condition
      A36-27 (STP1) - Body ground Stop light switch ON (Brake pedal depressed) 8 to 14 V
      A36-27 (STP1) - Body ground Stop light switch OFF (Brake pedal released) Below 1.5 V
      Fig 2: Identifying Skid Control ECU (STP1 Terminal)
      G05250429Courtesy 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 TERMINAL) 
    1. Turn the engine switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      A36-46 (IG1) - Body ground Engine switch on (IG) 10 to 14 V
      Fig 3: Identifying Skid Control ECU (IG1 Terminal)
      G05250423Courtesy 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 TERMINAL) 
    1. Turn the engine switch off.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      A36-32 (GND1) - Body ground Always Below 1 Ω
      A36-1 (GND2) - Body ground Always Below 1 Ω
      Fig 4: Identifying Skid Control ECU (GND Terminal)
      G05250408Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to Next Step 

  6. RECONFIRM DTC 
    1. Reconnect the skid control ECU connector.
    2. Clear the DTC (See DTC CHECK/CLEAR  ).
    3. Start the engine.
    4. Depress the brake pedal several times to test the stop light circuit.
    5. 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 

    A: CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) 

  7. 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

      Tester Connection Condition Specified Condition
      A40-2 - Body ground Always 10 to 14 V
      Fig 5: Identifying Stop Light Switch (Power Source Terminal)
      G05250432Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to Next Step 

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

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      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: Inspecting Stop Light Switch
      G04978071Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      RESULT REFERENCE

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

    B:  Go to step  13

    C: REPLACE STOP LIGHT SWITCH 

    A: Go to Next Step 

  9. INSPECT STOP LIGHT CONTROL RELAY 
    1. Remove the stop light control relay.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      3 - 4 Always Below 1 Ω
      Fig 7: Identifying Stop Light Control Relay Terminals
      G05250434Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE STOP LIGHT CONTROL RELAY 

    OK: Go to Next Step 

  10. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - ENGINE ROOM RELAY BLOCK) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      A40-1 - Stop light control relay terminal 4 Always Below 1 Ω
      A40-1 - Body ground Always 10 kΩ or higher
      Fig 8: Identifying A40 Stop Light Switch Connector And Engine Room Relay Block
      G05836789Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  11. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ENGINE ROOM RELAY BLOCK) 
    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

      Tester Connection Condition Specified Condition
      A36-27 (STP1) - Stop light control relay terminal 3 Always Below 1 Ω
      A36-27 (STP1) - Body ground Always 10 kΩ or higher
      Fig 9: Identifying A36 Skid Control ECU And Engine Room Relay Block
      G05836790Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  12. 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 

      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 

    A: INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) 

  13. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH) 
    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

      Tester Connection Condition Specified Condition
      A36-27 (STP1) - A40-1 Always Below 1 Ω
      A36-27 (STP1) - Body ground Always 10 kΩ or higher
      Fig 10: Identifying A36 Skid Control ECU And A40 Stop Light Switch Connectors
      G05250437Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  14. RECONFIRM DTC 
    1. Reconnect the skid control ECU connector and the stop light switch connector.
    2. Clear the DTC (See DTC CHECK/CLEAR  ).
    3. Start the engine.
    4. Depress the brake pedal several times to test the stop light circuit.
    5. 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 

    A: INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) 

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