VEHICLE STABILITY CONTROL SYSTEM, 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 (brake actuator assembly), the relay contact turns on and the stop light comes on.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1380

Stop Light Control Relay Malfunction

Either condition is met:

  1. When the voltage at the IG1 terminal is between 10 and 14 V and the stop light control relay drive output (STPO) is on, a signal has not been input to the STP terminal for 2 seconds or more.

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

  • ECU-IG NO.3 fuse

  • STOP fuse

  • Stop light switch circuit

  • Stop light control relay (STOP LP)

  • Stop light control relay circuit

  • Skid control ECU (Brake actuator assembly)

WIRING DIAGRAM

Refer to DTC C1425.

Click here

CAUTION / NOTICE / HINT

Note:

  • When replacing the skid control ECU (brake actuator assembly), perform calibration.

    Click here

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

Tip:

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

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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

      Result

      Result

      OK

      NG
    NG

    INSPECT STOP LIGHT CIRCUIT

    Click here

    OK

  2. CHECK TERMINAL VOLTAGE (STP TERMINAL)

    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

    2. Turn the ignition switch off.

    3. Disconnect the A64 skid control ECU (brake actuator assembly) connector.

    4. C199357C51

      *a

      Front view of wire harness connector

      (to Skid Control ECU [Brake Actuator Assembly])

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      A64-2 (STP) - Body ground

      Brake pedal depressed

      8 to 14 V

      Brake pedal released

      Below 1.5 V

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT)

    OK

  3. CHECK TERMINAL VOLTAGE (STP2 TERMINAL)

    1. Turn the ignition switch off.

    2. Make sure that there is no looseness in the locking part and connecting part of the connector.

    3. Disconnect the A64 skid control ECU (brake actuator assembly) connector.

    4. C199357C56

      *a

      Front view of wire harness connector

      (to Skid Control ECU [Brake Actuator Assembly])

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      A64-22 (STP2) - Body ground

      Brake pedal depressed

      8 to 14 V

      Brake pedal released

      Below 1.5 V

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STP2 CIRCUIT)

    OK

  4. PERFORM ACTIVE TEST USING GTS (STOP LIGHT RELAY)

    1. Reconnect the A64 skid control ECU (brake actuator assembly) connector.

    2. Connect the GTS to the DLC3.

    3. Start the engine.

    4. Turn the GTS on.

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

    6. While performing the Active Test, check the illumination condition of the stop lights and "Stop Light Relay Output" in the Data List.

    Chassis > ABS/VSC/TRC > Active Test

    Tester Display

    Measurement Item

    Control Range

    Diagnostic Note

    Stop Light Relay

    Stop light control relay (STOP LP)

    Relay ON/OFF

    Stop lights come on

    Vehicle condition: Vehicle stopped

    Chassis > ABS/VSC/TRC > Data List

    Tester Display

    Measurement Item

    Range

    Normal Condition

    Diagnostic Note

    Stop Light Relay Output

    Stop light control relay (STOP LP) output

    ON or OFF

    OFF: Relay output off (Stop lights off)

    ON: Relay output on (Stop lights on)

    -

    Chassis > ABS/VSC/TRC > Active Test

    Active Test Display

    Stop Light Relay

    Data List Display

    Stop Light Relay Output

    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

    INSPECT STOP LIGHT CONTROL RELAY (STOP LP)Click here

    A

  5. RECONFIRM DTC

    1. Turn the ignition switch off.

    2. Clear the DTCs.

      Click here

      Chassis > ABS/VSC/TRC > Clear DTCs

    3. Start the engine.

    4. Perform a road test.

    5. Check if the same DTC is output.

      Click here

      Chassis > ABS/VSC/TRC > Trouble Codes

      Result

      Proceed to

      DTC C1380 is not output

      DTC C1380 is output
    DTC C1380 is not output

    USE SIMULATION METHOD TO CHECK

    Click hereClick hereClick hereClick here

    DTC C1380 is output

    REPLACE BRAKE ACTUATOR ASSEMBLY

    Click here

  6. INSPECT STOP LIGHT CONTROL RELAY (STOP LP)

    1. Remove the stop light control relay (STOP LP) from the No. 2 engine room relay block assembly.

    2. A087121C01

      *1

      Stop Light Control Relay (STOP LP)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      3 - 4

      Battery positive voltage is applied to terminal 1 and battery negative voltage is applied to terminal 2

      10 kΩ or higher

      Battery positive voltage is not applied to terminal 1 and battery negative voltage is not applied to terminal 2

      Below 1 Ω

      3 - 5

      Battery positive voltage is applied to terminal 1 and battery negative voltage is applied to terminal 2

      Below 1 Ω

      Battery positive voltage is not applied to terminal 1 and battery negative voltage is not applied to terminal 2

      10 kΩ or higher

      Result

      Result

      OK

      NG
    NG

    REPLACE STOP LAMP CONTROL RELAY (STOP LP)

    OK

  7. CHECK TERMINAL VOLTAGE (STOP LIGHT POWER SOURCE TERMINAL)

    1. C279052C01

      *a

      Component without Stop Light Control Relay (STOP LP)

      (No. 2 Engine Room Relay Block Assembly)

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      5 - Body ground

      Always

      11 to 14 V

      2 - Body ground

      Ignition switch ON

      11 to 14 V

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK TERMINAL VOLTAGE (STPO TERMINAL)

    1. Install the stop light control relay (STOP LP).

    2. Make sure that there is no looseness in the locking part and connecting part of the connector.

    3. Disconnect the A64 skid control ECU (brake actuator assembly) connector.

    4. Turn the ignition switch to ON.

    5. C199357C52

      *a

      Front view of wire harness connector

      (to Skid Control ECU [Brake Actuator Assembly])

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      A64-31 (STPO) - Body ground

      Ignition switch ON

      11 to 14 V

      Result

      Result

      OK

      NG
    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STPO CIRCUIT)