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DTC C1380: Stop Light Control Relay Malfunction: Procedure

  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 Illumination Condition
      Brake pedal depressed ON
      Brake pedal released OFF

    NG → See step   6 

    OK: Go to next step 

  2. READ VALUE USING TECHSTREAM (STOP LIGHT SW) 
    1. Turn the engine switch off.
    2. Connect the Techstream to the DLC3.
    3. Start the engine.
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.
      ABS/VSC/TRAC

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light SW Stop light switch / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released      		 -
    6. Check that the stop light switch condition observed on the Techstream changes according to brake pedal operation.

      OK

      The Techstream displays ON or OFF according to brake pedal operation.

    NG → See step   9 

    OK: Go to next step 

  3. PERFORM ACTIVE TEST USING TECHSTREAM (STOP LIGHT RELAY) 
    1. Turn the engine switch off.
    2. Connect the Techstream to the DLC3.
    3. Start the engine.
    4. Turn the Techstream on.
    5. Enter the following menus: Chassis / ABS/VSC/TRAC / Active Test.
      ABS/VSC/TRAC

      Tester Display Test Part Control Range Diagnostic Note
      Stop Light Relay No. 2 integration relay Relay ON/OFF Observe the stop light (the stop lights do not come on for 2 to 5 seconds).
    6. While performing the Active Test, check the illumination condition of the stop lights and "Stop Light Relay Output" in the Data List.
      ABS/VSC/TRAC

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light Relay Output No. 2 integration relay output / ON or OFF ON: Relay output ON
      OFF: Relay output OFF      		 -
      RESULT

      Result Proceed to
      When Active Test performed, Data List item changes between ON and OFF, but stop lights do not turn on A
      When Active Test performed, Data List item changes between ON and OFF and stop lights turn on and off B

    B → See step   10 

    A: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (STP2 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 (brake actuator assembly) connector.
      GTY415980Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A13-22 (STP2) - Body ground Brake pedal depressed 8 to 14 V
      Brake pedal released Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU [Brake Actuator Assembly])

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. RECONFIRM DTC 
    1. Reconnect the skid control ECU (brake actuator assembly) connector.
    2. Clear the DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .
    3. Turn the engine switch off.
    4. Start the engine.
    5. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR [12/2011 - ] .
      RESULT

      Result Proceed to
      DTC (C1380) is not output A
      DTC (C1380) is output B

    B → See step   13 

    A → See step   12 

  6. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY POWER SOURCE TERMINAL) 
    1. Turn the engine switch off.
      GTY397562Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the No. 2 integration relay connectors.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2B-7 (BATT) - Body ground Always 11 to 14 V
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2A-22 (GNDA) - Body ground Always Below 1 Ω
      2B-10 (GNDB) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 2 Integration Relay)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (BATTERY - NO. 2 INTEGRATION RELAY) 
    1. Turn the engine switch off.
    2. Disconnect the No. 2 integration relay connector.
      GTY399308Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      2A-11 (STPO) - Body ground Brake pedal depressed 8 to 14 V
      Brake pedal released Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to No. 2 Integration Relay)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY - SKID CONTROL ECU) 
    1. Turn the engine switch off.
    2. Disconnect the 2A No. 2 integration relay connector.
    3. Disconnect the A13 skid control ECU (brake actuator assembly) connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2A-3 (STOP) - A13-22 (STP2) Always Below 1 Ω
      2A-3 (STOP) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   14 

  9. CHECK HARNESS AND CONNECTOR (STP 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.
      GTY397222Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Disconnect the skid control ECU (brake actuator assembly) connector.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A13-2 (STP) - Body ground Brake pedal depressed 8 to 14 V
      Brake pedal released Below 1.5 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU [Brake Actuator Assembly])

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY - SKID CONTROL ECU) 
    1. Turn the engine switch off.
    2. Disconnect the 2A No. 2 integration relay connector.
    3. Disconnect the A13 skid control ECU (brake actuator assembly) connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2A-7 (ACC) - A13-31 (STPO) Always Below 1 Ω
      2A-7 (ACC) - Body ground Always 10 kΩ or higher
      2A-18 (ESS) - A13-8 (EXO)* Always Below 1 Ω
      2A-18 (ESS) - Body ground* Always 10 kΩ or higher
      1. *: w/ Emergency Brake Signal

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (NO. 2 INTEGRATION RELAY - SKID CONTROL ECU) 
    1. Turn the engine switch off.
    2. Disconnect the 2A No. 2 integration relay connector.
    3. Disconnect the A13 skid control ECU (brake actuator assembly) connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      2A-3 (STOP) - A13-22 (STP2) Always Below 1 Ω
      2A-3 (STOP) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   14 

  12. CHECK FOR INTERMITTENT PROBLEMS. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2011 - ] 
  13. REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  REMOVAL [12/2011 - ] 
  14. REPLACE NO. 2 INTEGRATION RELAY. Refer to  REMOVAL [12/2011 - ] 
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