VEHICLE STABILITY CONTROL SYSTEM (for Hydraulic Brake Booster), Diagnostic DTC:C1380

DTC Code DTC Name
C1380 Stop Light Control Relay Malfunction

DESCRIPTION

Upon receiving the hill-start assist control operating signal from the skid control ECU (master cylinder solenoid), the stop light control ECU contact turns on and the stop light comes on.

DTC Code DTC Detection Condition Trouble Area
C1380

Either condition is met:


  1. When the voltage at the IG1 terminal is between 10 and 14 V and the stop light control ECU assembly drive output (STPO) is on, a signal is not input to the STP2 terminal for 5 seconds or more.

  2. When the voltage at the IG1 terminal is between 10 and 14 V and the stop light control ECU assembly drive output (STPO) is off, the signal at the STP terminal is different from the input signal at the STP2 terminal for 5 seconds or more.

  • STOP fuse

  • Stop light switch circuit

  • Stop light control ECU assembly

  • Stop light control ECU circuit

  • Skid control ECU (Master cylinder solenoid)

WIRING DIAGRAM

A01DM4KE01

INSPECTION PROCEDURE

Note


  • When replacing the skid control ECU (master cylinder solenoid), perform calibration Click here.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Tech Tips

When DTC C1425 is output together with DTC C1380, inspect and repair the trouble areas indicated by DTC C1425 first Click here.

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

    CHECK TERMINAL VOLTAGE AND RESISTANCE (+B, GND) Click here

    OK

  2. READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SW)


    1. Turn the ignition switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the intelligent tester on.

    5. Enter the following menus: Chassis / ABS/VSC/TRC / Data List.

      ABS/VSC/TRC
      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 intelligent tester changes according to brake pedal operation.

      OK
      The intelligent tester displays ON or OFF according to brake pedal operation.

    NG

    CHECK TERMINAL VOLTAGE (STP) Click here

    OK

  3. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (STOP LIGHT RELAY)


    1. Turn the ignition switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the intelligent tester on.

    5. Enter the following menus: Chassis / ABS/VSC/TRC / Active Test.

      ABS/VSC/TRC
      Tester Display Test Part Control Range Diagnostic Note
      Stop Light Relay Stop light control ECU ECU ON/OFF Observe 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/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light Relay Output Stop light control ECU output/ ON or OFF

      ON: Stop light control ECU on (Stop lights on)

      OFF: Stop light control ECU off (Stop lights off)

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

    B

    CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - STOP LIGHT CONTROL ECU ASSEMBLY) Click here

    A

  4. CHECK TERMINAL VOLTAGE (STP2)


    1. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

    2. A01DRS6E30
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU [Master Cylinder Solenoid])

      Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A7-45 (STP2) - Body ground Brake pedal depressed 8 to 14 V
      Brake pedal released Below 1.5 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. RECONFIRM DTC


    1. Clear the DTCs Click here.

    2. Start the engine.

    3. Perform a road test.

    4. Check if the same DTC is output Click here.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (for LHD) B
      DTC is output (for RHD) C

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

    A

    USE SIMULATION METHOD TO CHECK Click here

  6. CHECK TERMINAL VOLTAGE AND RESISTANCE (+B, GND)


    1. Disconnect the A54 stop light control ECU assembly connector.

    2. A01DR4FE04
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Stop Light Control ECU Assembly)

      Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A54-6 (+B) - Body ground Always 11 to 14 V

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A54-8 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK TERMINAL VOLTAGE (STP)


    1. Disconnect the A54 stop light control ECU assembly connector.

    2. A01DR4FE05
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Stop Light Control ECU Assembly)

      Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A54-5 (STP) - Body ground Brake pedal depressed 8 to 14 V
      Brake pedal released Below 1.5 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (STOP LIGHT CONTROL ECU ASSEMBLY - MASTER CYLINDER SOLENOID)


    1. Disconnect the A54 stop light control ECU assembly connector.

    2. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A54-1 (OUT) - A7-45 (STP2) Always Below 1 Ω
      A54-1 (OUT) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE STOP LIGHT CONTROL ECU ASSEMBLY Click here

  9. CHECK TERMINAL VOLTAGE (STP)


    1. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

    2. A01DRS6E31
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Skid Control ECU [Master Cylinder Solenoid])

      Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A7-7 (STP) - Body ground Brake pedal depressed 8 to 14 V
      Brake pedal released Below 1.5 V
      Result
      Result Proceed to
      NG A
      OK (for LHD) B
      OK (for RHD) C

    B

    REPLACE MASTER CYLINDER SOLENOID Click here

    C

    REPLACE MASTER CYLINDER SOLENOID Click here

    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  10. CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - STOP LIGHT CONTROL ECU ASSEMBLY)


    1. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

    2. Disconnect the A54 stop light control ECU assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-16 (STP0) - A54-9 (ACC) Always Below 1 Ω
      A7-16 (STP0) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. CHECK HARNESS AND CONNECTOR (MASTER CYLINDER SOLENOID - STOP LIGHT CONTROL ECU ASSEMBLY)


    1. Disconnect the A7 skid control ECU (master cylinder solenoid) connector.

    2. Disconnect the A54 stop light control ECU assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A7-45 (STP2) - A54-1 (OUT) Always Below 1 Ω
      A7-45 (STP2) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE STOP LIGHT CONTROL ECU ASSEMBLY Click here