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Inspection Procedure

NOTE: When replacing the skid control ECU, perform zero point calibration and store system information (See CALIBRATION  ).
  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 REFERENCE CHART

      Condition Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

    NG :  Go to step  6

    OK : Go to next step 

  2. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH AND BRAKE PEDAL LOAD SENSING SWITCH) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Select the Data List mode on the Techstream (See DATA LIST/ACTIVE TEST  ).

      ABS/VSC/TRAC 

      TESTER DISPLAY REFERENCE CHART

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Lamp SW Stop light switch/ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released      		 -
      Brake Pedal Load Sensing 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      		 -
    4. Check that the stop light display observed on the Techstream changes when the brake pedal is depressed.

      OK: 

      When the brake pedal is depressed, the Techstream displays "ON". 

    5. Depress the brake pedal slowly, 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 

      RESULT REFERENCE

      Result Proceed to
      OK A
      NG (The stop light switch does not turn on) B
      NG (The brake pedal load sensing switch turns on first) C

    B :  Go to step  11

    C :  Go to step  12

    A : Go to next step 

  3. INSPECT SKID CONTROL ECU (IG1 TERMINAL) 
    1. Turn the engine switch off.
    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    3. Disconnect the skid control ECU connector.
    4. Turn the engine switch on (IG).
    5. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      STANDARD VOLTAGE

      Tester Connection Switch Condition Specified Condition
      K93-1 (161) - Body ground Engine switch on (IG) 11 to 14 V

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

    Fig 1: Inspecting Skid Control ECU (IG1 Terminal)
    G05807039Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to next step 

  4. INSPECT SKID CONTROL ECU (GND TERMINAL) 
    1. Turn the engine switch off.
    2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    3. Disconnect the skid control ECU connectors.
    4. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      A57-26 (GND1) - Body ground Always Below 1 Ω
      A57-14 (GND2) - Body ground Always Below 1 Ω
      A58-22 (GND3) - Body ground Always Below 1 Ω

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

    Fig 2: Inspecting Skid Control ECU (GND Terminal)
    G05807040Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to next step 

  5. RECONFIRM DTC 
    1. Reconnect the skid control ECU connectors.
    2. Clear the DTCs (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

      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 SKID CONTROL ECU  (See REMOVAL  )

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

  6. INSPECT STOP SW FUSE 
    1. Remove the STOP SW fuse from the main body ECU RH (cowl side junction block RH).
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      STOP SW (7.5 A) fuse Always Below 1 Ω

    NG : REPLACE STOP SW FUSE 

    Fig 3: Inspecting Stop SW Fuse
    G05752624Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to next step 

  7. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL) 
    1. Install the STOP SW fuse.
    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    3. Disconnect the stop light switch connector.
    4. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      STANDARD VOLTAGE

      Tester Connection Condition Specified Condition
      A35-2 - Body ground Always 11 to 14 V

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

    Fig 4: Inspecting Stop Light Switch (Power Source Terminal)
    G05807051Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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

      Tester Connection Switch Condition Specified Condition
      1-2 Switch pin free Below 1 Ω
      1-2 Switch pin pushed in 10 kΩ or higher

    NG : REPLACE STOP LIGHT SWITCH 

    Fig 5: Inspecting Stop Light Switch
    G05750570Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to next step 

  9. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    2. Disconnect the skid control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      K93-10 (STP) - A35-1 Always Below 1 Ω

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 6: Checking Harness And Connector (Skid Control ECU - Stop Light Switch)
    G05807053Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : Go to next step 

  10. RECONFIRM DTC 
    1. Reconnect the skid control ECU connector and the stop light switch connector.
    2. Clear the DTCs (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

      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 SKID CONTROL ECU  (See REMOVAL  )

    A : INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT)  (See PROBLEM SYMPTOMS TABLE )

  11. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - STOP LIGHT SWITCH) 
    1. Turn the engine switch off.
    2. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    3. Disconnect the skid control ECU connector and the stop light switch connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      K93-10 (STP) - A35-1 Always Below 1 Ω

      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  ).

    NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 7: Checking Harness And Connector (Skid Control ECU - Stop Light Switch)
    G05807053Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : REPLACE SKID CONTROL ECU  (See REMOVAL  )

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

      OK: 

      The brake pedal height and stop light switch installation are normal. 

      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  ).

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

    OK : REPLACE BRAKE PEDAL SUPPORT ASSEMBLY (BRAKE PEDAL LOAD SENSING SWITCH)  (See REMOVAL )

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