VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1425

DTC Code DTC Name
C1425 Open in Stop Light Switch Circuit

DESCRIPTION

The skid control ECU detects the brake operating conditions through a signal transmitted by the stop light switch.

The skid control ECU has an open detection circuit, which outputs this DTC when detecting an open in the stop light input line or the ground line of the stop light circuit with the stop light switch off (brake pedal not depressed).

On vehicles equipped with the Stop and Start System, DTC may be output if there is a significant difference between IG power source voltage and backup boost converter power source voltage when the stop and start system is cranking the engine during restarting.

DTC Code DTC Detection Condition Trouble Area
C1425 When IG1 terminal voltage is between 9.5 and 17.4 V, an open stop light switch circuit continues for 3 seconds or more.

  • STOP fuse

  • Stop light switch

  • Stop light switch circuit

  • Brake actuator assembly (Skid control ECU)

WIRING DIAGRAM

A01198XE01

INSPECTION PROCEDURE

Note


  • When replacing the brake actuator assembly, perform zero point calibration Click here.

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

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SWITCH)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

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

      ABS/VSC/TRC (Skid Control ECU)
      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

      		 -

    4. Check that the stop light switch display 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

    INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL) Click here

    OK

  2. RECONFIRM DTC


    1. Turn the ignition switch off.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Depress the brake pedal several times to test the stop light circuit.

    5. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTC (C1425) is not output A
      DTC (C1425) is output B

      Tech Tips

      If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step Click here.


    B

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Click here

  3. INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL)


    1. A011A8HE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Stop Light Switch)

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

    2. Disconnect the A27 stop light switch connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A27-2 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

    OK

  4. INSPECT STOP LIGHT SWITCH


    1. A011984E17
      Text in Illustration
      *1

      Component without harness connected

      (Stop Light Switch)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 - 2 Switch pin free Below 1 Ω
      1 - 2 Switch pin pushed in 10 kΩ or higher

    NG

    REPLACE STOP LIGHT SWITCH Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (STP TERMINAL)


    1. A01196QE16
      Text in Illustration
      *A for LHD
      *B for RHD
      *1

      Front view of wire harness connector

      (to Skid Control ECU)

      Turn the ignition switch off.

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

    3. Disconnect the skid control ECU connector.

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

      Standard Voltage
      for LHD
      Tester Connection Switch Condition Specified Condition
      A16-2 (STP) - Body ground

      Stop light switch ON

      (Brake pedal depressed)

      		 8 to 14 V
      A16-2 (STP) - Body ground

      Stop light switch OFF

      (Brake pedal released)

      		 Below 1.5 V
      for RHD
      Tester Connection Switch Condition Specified Condition
      A17-2 (STP) - Body ground

      Stop light switch ON

      (Brake pedal depressed)

      		 8 to 14 V
      A17-2 (STP) - Body ground

      Stop light switch OFF

      (Brake pedal released)

      		 Below 1.5 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here