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Home >> Toyota >> 2008 >> Tacoma PreRunner, 2D Pickup >> Repair and Diagnosis >> Brakes >> Traction Control >> Brake Control >> Vehicle Stability Control System >> DTC C1380/64 Stop Light Control Relay Malfunction >> Inspection Procedure
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Inspection Procedure

NOTE: When replacing the master cylinder solenoid, 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 go off when the brake pedal is released.

      OK 

      BRAKE PEDAL CONNDITION CHART

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

      HINT:

      Check the stop light bulbs as they may have burnt out.

    NG:  Go to step  10

    OK: Go To Next Step 

  2. INSPECT SKID CONTROL ECU (STP TERMINAL VOLTAGE) 
    1. Disconnect the skid control ECU connector.
    2. Measure the voltage.

      Standard Voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Switch condition Specified Condition
      S1-7 (STP) - Body ground Brake pedal depressed 8 to 16 V
      S1-7 (STP) - Body ground Brake pedal released Below 1.5 V
    3. Reconnect the skid control ECU connector.

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

    Fig 1: Identifying Skid Control ECU Connector
    G05199252Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  3. INSPECT SKID CONTROL ECU (STP2 TERMINAL VOLTAGE) 
    1. Disconnect the skid control ECU connector.
    2. Measure the resistance.

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      S1-7 (STP) - S1-45 (STP2) Below 1 Ω
    3. Reconnect the skid control ECU connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STP2 CIRCUIT) 

    Fig 2: Identifying Skid Control ECU Connector
    G05199279Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  4. PERFORM ACTIVE TEST BY TECHSTREAM (STOP LIGHT RELAY) 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch to the ON position.
    3. Turn Techstream ON.
    4. Select the Active Test mode on Techstream.

      ABS/VSC/TRAC 

      ABS/VSC/TRAC - ACTIVE TEST

      Tester Display Test part Control Range Diagnostic Note
      Stop Light Relay Turns stop light relay ON/OFF Observe stop lights
    5. Check that the stop lights turn on and off on the rear combination light when using Techstream.

      OK: The stop lights turn on and off according to Techstream operations. 

    NG:  Go to step  6

    OK: Go To Next Step 

  5. RECONFIRM DTC 
    1. Clear the DTCs (See DTC CHECK/CLEAR  ).
    2. Check if the same DTCs are recorded.
      DTC OUTPUT REFERENCE

      Result Proceed To
      DTC output A
      DTC not output B

    B: END 

    A: REPLACE MASTER CYLINDER SOLENOID 

  6. CHECK STOP LIGHT CONTROL RELAY 
    1. Disconnect the STOP LP CTRL relay.
    2. Turn the ignition switch to the ON position.
    3. Measure the voltage.

      Standard Voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      Terminal 5 - Body ground Always 8 to 16 V
      Terminal 1 - Body ground Always 8 to 16 V
      Fig 3: Identifying Stop Light Control Relay Connector
      G05678185Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Turn the ignition switch to OFF.
    5. Reconnect the STOP LP CTRL relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LP CTRL RELAY) 

    OK: Go To Next Step 

  7. INSPECT STOP LIGHT CONTROL RELAY 
    1. Remove the STOP LP CTRL relay from the engine room R/B and J/B.
    2. Measure the resistance.

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3 - 4 Below 1 Ω
      3 - 5 10 kΩ or higher
    3. Apply the battery voltage between terminals 1 (+) and 2
    4. Measure the resistance.
      Fig 4: Inspecting Stop Light Control Relay
      G04965497Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3 - 4 10 kΩ or higher
      3 - 5 Below 1 Ω
    5. Reinstall the STOP LP CTRL relay.

    NG: REPLACE STOP LIGHT CONTROL RELAY 

    OK: Go To Next Step 

  8. INSPECT MASTER CYLINDER SOLENOID (STPO TERMINAL VOLTAGE) 
    1. Disconnect the skid control ECU connector.
    2. Turn the ignition switch to the ON position.
    3. Measure the voltage.

      Standard Voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      S1-16 (STPO) - Body ground Brake pedal depressed 10 to 14 V
    4. Turn the ignition switch to OFF.
    5. Reconnect the skid control ECU connector.

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

    Fig 5: Identifying Skid Control ECU Connector
    G05199282Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  9. RECONFIRM DTC 
    1. Clear the DTCs (See DTC CHECK/CLEAR  ).
    2. Check if the same DTCs are recorded.
      DTC OUTPUT REFERENCE

      Result Proceed To
      DTC output A
      DTC not output B

    B: END 

    A: REPLACE MASTER CYLINDER SOLENOID 

  10. CHECK STOP LIGHT SWITCH ASSEMBLY (STOP LIGHT SWITCH POWER SOURCE TERMINAL VOLTAGE) 
    1. Disconnect the stop light switch connector.
    2. Turn the ignition switch to the ON position.
    3. Measure the voltage.

      Standard Voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      S10-2 Body ground 10 to 14 V
    4. Turn the ignition switch to OFF.
    5. Reconnect the stop light switch connector.

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

    Fig 6: Identifying Stop Light Switch Connector
    G05199283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  11. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Disconnect the stop light switch connector.
    2. Measure the resistance.

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      Switch condition Tester connection Specified condition
      Switch pin free 1 - 2 Below 1 Ω
      Switch pin pushed in 1 - 2 10 kΩ or higher
    3. Reconnect the stop light switch connector.

    NG: REPLACE STOP LIGHT SWITCH ASSEMBLY 

    Fig 7: Inspecting Stop Light Switch Assembly
    G05199133Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  12. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - STOP LP CTRL RELAY) 
    1. Remove the STOP LP CTRL relay.
    2. Measure the resistance.

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      S10-2 - STOP LP CTRL relay (5) Below 1 Ω
      S10-2-Body ground 10 kΩ or higher
    3. Reinstall the STOP LP CTRL relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 8: Identifying Stop Light Switch Connector & STOP LP CTRL Relay
    G05199285Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go To Next Step 

  13. INSPECT STOP LIGHT CONTROL RELAY 
    1. Remove the STOP LP CTRL relay from the engine room R/B and J/B.
    2. Measure the resistance.

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3 - 4 Below 1 Ω
      3 - 5 10 kΩ or higher
    3. Apply the battery voltage between terminals 1 (+) and 2 (-).
    4. Measure the resistance.
      Fig 9: Inspecting Stop Light Control Relay
      G04965497Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      3 - 4 10 kΩ or higher
      3 - 5 Below 1 Ω
    5. Reinstall the STOP LP CTRL relay.

    NG: REPLACE STOP LIGHT CONTROL RELAY 

    OK: Go To Next Step 

  14. CHECK HARNESS AND CONNECTOR (REAR COMBINATION LIGHT - STOP LP CTRL RELAY) 
    1. Disconnect the rear combination light connector.
    2. Remove the STOP LP CTRL relay.
    3. Measure the resistance.

      Standard Resistance (LH) 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      R5-1 - STOP LP CTRL (4) Below 1 Ω
      R5-1 - Body ground 10 kΩ or higher
      R5-6 - Body ground Below 1 Ω

      Standard Resistance (RH) 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      R6-1 - STOP LP CTRL (4) Below 1 Ω
      R6-1 - Body ground 10 kΩ or higher
      R6-6 - Body ground Below 1 Ω
    4. Reinstall the STOP LP CTRL relay.
    5. Reconnect the rear combination light connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 10: Identifying Rear Combination Light Connector & STOP LP CTRL Relay
    G05199287Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

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