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Dtc C1380-7F: Stop Lamp Relay Actuator Stuck Off [11/2021 - ]: Procedure

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  1. Perform Active Test Using Gts (Stop Lamp Relay) 
    1. Perform The Stop Light Control Relay (Semiconductor Power Integration ECU) Active Test, And Confirm That The Value Of "Stop Light Sw" Changes.

      Chassis > Brake/Epb > Active Test 

      Tester Display Measurement Item Control Range Restrict Condition Diagnostic Note
      Stop Lamp Relay Stop Light Control Relay (Semiconductor Power Integration ECU) Off / On Vehicle Condition: Vehicle Stopped
      Hint: 
      To Protect This Actuator And Solenoid, This Test Will Only Last 5 Seconds.      		 With The Brake Pedal Released, Check That The Stop Lights Illuminate And The Value Of Stop Light Relay On The Gts Changes To On When Stop Lamp Relay Is On

      Chassis > Brake/Epb > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Stop Light Sw Stop Light Switch Assembly Status
      (Stp Or Stp2 Terminal Input)      		 Off / On Off: Brake Pedal Released
      On: Brake Pedal Depressed      		 Hint: 
      • Stop Light Control Relay (Semiconductor Power Integration ECU) Off: Stp Terminal Status Displayed.
      • Stop Light Control Relay (Semiconductor Power Integration ECU) On: Stp2 Terminal Status Displayed.

      Chassis > Brake/Epb > Active Test 

      Active Test Display
      Stop Lamp Relay
      Data List Display
      Stop Light Sw

      Result

      Result Proceed To
      The Value Of Stop Light Sw Is Off. A
      The Value Of Stop Light Sw Is On. B

    Result: 

    B 

    Replace Brake Actuator Assembly. Refer To  Removal [11/2021 - ] 

    Result: 

    A 

    See Step  2

  2. Perform Active Test Using Gts (Stop Lamp Relay) 
    1. Perform The Stop Light Control Relay (Semiconductor Power Integration ECU) Active Test, And Confirm That The Stop Lights Illuminate.

      Chassis > Brake/Epb > Active Test 

      Tester Display Measurement Item Control Range Restrict Condition Diagnostic Note
      Stop Lamp Relay Stop Light Control Relay (Semiconductor Power Integration ECU) Off / On Vehicle Condition: Vehicle Stopped
      Hint: 
      To Protect This Actuator And Solenoid, This Test Will Only Last 5 Seconds.      		 With The Brake Pedal Released, Check That The Stop Lights Illuminate And The Value Of Stop Light Relay On The Gts Changes To On When Stop Lamp Relay Is On

      Chassis > Brake/Epb > Active Test 

      Tester Display
      Stop Lamp Relay

      Result

      Result Proceed To
      The Stop Lights Are Not Illuminated. A
      The Stop Lights Are Illuminated. B

    Result: 

    B 

    See Step  9

    Result: 

    A 

    See Step  3

  3. Check Harness And Connector (Semiconductor Power Integration ECU - Brake Actuator Assembly) 
    1. Turn The Ignition Switch Off.
    2. Make Sure That There Is No Looseness At The Locking Part And The Connecting Part Of The Connectors.

      Ok

      The Connector Is Securely Connected.

    3. Disconnect The A38 No. 2 Skid Control ECU (Brake Actuator Assembly) Connector.
    4. Check Both The Connector Case And The Terminals For Deformation And Corrosion.

      Ok

      No Deformation Or Corrosion.

    5. Measure The Voltage According To The Value(S) In The Table Below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A38-32 (Stpo) - Body Ground Always 11 To 14 V

      Result

      Proceed To
      Ok
      Ng

    Result: 

    Ng 

    See Step  8

    Result: 

    Ok 

    See Step  4

  4. Check Brake Actuator Assembly 
    1. Measure The Voltage According To The Value(S) In The Table Below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A38-37 (Stp2) - Body Ground Stop Light Switch Assembly On (Brake Pedal Depressed) 11 To 14 V

      Result

      Proceed To
      Ok
      Ng

    Result: 

    Ok 

    Replace Brake Actuator Assembly. Refer To  Removal [11/2021 - ] 

    Result: 

    Ng 

    See Step  5

  5. Check For Short To Ground In Stp2 Circuit 
    1. Check That There Is No Short To Ground In The Stp2 Circuit (Wire Harnesses, Connectors, Semiconductor Power Integration ECU And Stop Lights)

      Ok

      There Is No Short To Ground.

      Result

      Proceed To
      Ok
      Ng

    Result: 

    Ng 

    Repair Or Replace Malfunctioning Part 

    Result: 

    Ok 

    See Step  6

  6. Check Harness And Connector (Semiconductor Power Integration ECU - Brake Actuator Assembly) 
    1. Make Sure That There Is No Looseness At The Locking Part And The Connecting Part Of The Connectors.

      Ok

      The Connector Is Securely Connected.

    2. Disconnect The A77 Semiconductor Power Integration ECU Connector.
    3. Check Both The Connector Case And The Terminals For Deformation And Corrosion.

      Ok

      No Deformation Or Corrosion.

    4. Measure The Resistance According To The Value(S) In The Table Below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A77-18 (Out) - A38-37 (Stp2) Always Below 1 Ω

      Result

      Proceed To
      Ok
      Ng

    Result: 

    Ng 

    Repair Or Replace Harness Or Connector 

    Result: 

    Ok 

    See Step  7

  7. Check Harness And Connector (Semiconductor Power Integration ECU - Brake Actuator Assembly) 
    1. Measure The Resistance According To The Value(S) In The Table Below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A77-10 (Stp) - A38-11 (Stp) Always Below 1 Ω

      Result

      Proceed To
      Ok
      Ng

    Result: 

    Ok 

    Replace Semiconductor Power Integration ECU. Refer To  Removal [11/2021 - ] 

    Result: 

    Ng 

    Repair Or Replace Harness Or Connector 

  8. Check Semiconductor Power Integration ECU 
    1. Make Sure That There Is No Looseness At The Locking Part And The Connecting Part Of The Connectors.

      Ok

      The Connector Is Securely Connected.

      GTY1060075Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A Component With Harness Connected
      (Semiconductor Power Integration ECU)
    2. Measure The Voltage According To The Value(S) In The Table Below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A77-8 (Acc) - Body Ground Always 11 To 14 V

      Result

      Proceed To
      Ok
      Ng

    Result: 

    Ok 

    Repair Or Replace Harness Or Connector 

    Result: 

    Ng 

    Replace Semiconductor Power Integration ECU. Refer To  Removal [11/2021 - ] 

  9. Check Brake Actuator Assembly 
    1. Turn The Ignition Switch Off.
    2. Make Sure That There Is No Looseness At The Locking Part And The Connecting Part Of The Connectors.

      Ok

      The Connector Is Securely Connected.

    3. Disconnect The A38 No. 2 Skid Control ECU (Brake Actuator Assembly) Connector.
    4. Check Both The Connector Case And The Terminals For Deformation And Corrosion.

      Ok

      No Deformation Or Corrosion.

    5. Measure The Voltage According To The Value(S) In The Table Below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A38-37 (Stp2) - Body Ground Stop Light Switch Assembly On (Brake Pedal Depressed) 11 To 14 V

      Result

      Proceed To
      Ok
      Ng

    Result: 

    Ok 

    Replace Brake Actuator Assembly. Refer To  Removal [11/2021 - ] 

    Result: 

    Ng 

    Repair Or Replace Harness Or Connector 

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