ECD SYSTEM(w/ DPF), Diagnostic DTC:P0724

DTC Code DTC Name
P0724 Brake Switch "B" Circuit High

DESCRIPTION

The stop light switch is part of a duplex system that transmits two signals: STP and ST1-. These two signals are used by the ECM to monitor whether or not the brake system is working properly. This DTC indicates that the stop light switch remains on. When the stop light switch remains on during GO and STOP driving, the ECM interprets this as a fault in the stop light switch. Then the MIL illuminates and the ECM stores the DTC.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0724 Brake Switch "B" Circuit High Stop light switch remains on even when vehicle is driven in GO (30 km/h (19 mph) or more) and STOP (less than 3 km/h (1.8 mph)) pattern 5 times (2 trip detection logic).

  • Short in stop light switch signal circuit

  • Stop light switch assembly

  • ECM

 Comes on DTC stored
Related Data List
DTC No. Data List
P0724 Stop Light Switch

CONFIRMATION DRIVING PATTERN

DTC No. DTC Detection Drive Pattern
P0724 Accelerate the vehicle to 30 km/h (19 mph) or more, depress the brake pedal and decelerate the vehicle to 3 km/h (1.8 mph) or less 5 times.

WIRING DIAGRAM

Refer to DTC P0504.

Click here

CAUTION / NOTICE / HINT

Note

After replacing the ECM, the new ECM needs registration (Click here ) and initialization Click here.

Tech Tips

Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. READ VALUE USING GTS (STOP LIGHT SWITCH)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Stop Light Switch.


      Powertrain > Engine and ECT > Data List
      Tester Display
      Stop Light Switch

    4. Read the value displayed on the GTS when the brake pedal is depressed and released.

      OK
      Brake Pedal Display
      Released OFF
      Depressed ON
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 6 Click here

    NG

  2. INSPECT STOP LAMP SWITCH ASSEMBLY


    1. Inspect the stop light switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE STOP LAMP SWITCH ASSEMBLY Click here

    OK

  3. CHECK ECM (STP VOLTAGE)


    1. B00252QC34
      *a Brake Pedal Depressed
      *b Brake Pedal Released
      *c

      Component with harness connected

      (ECM)

      Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Brake Pedal Condition Specified Condition
      G86-13 (STP) - Body ground Released 0 to 1.5 V
      Depressed 7.5 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  4. REPLACE ECM


    1. Replace the ECM.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 6 Click here

  5. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.

      Result
      Proceed to
      NEXT

    NEXT

  6. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the GTS to the DLC3.

    2. Clear the DTCs.


      Powertrain > Engine and ECT > Clear DTCs

    3. Turn the ignition switch off for 30 seconds or more.

    4. Turn the ignition switch to ON and turn the GTS on.

    5. Start the engine.

    6. Accelerate the vehicle to 30 km/h (19 mph) or more, depress the brake pedal and decelerate the vehicle to 3 km/h (1.8 mph) or less 5 times or more.

    7. Confirm that the DTC is not output again.

      Tech Tips

      Perform the following procedure using the GTS to determine whether or not the DTC judgment has been carried out.


      1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.


        Powertrain > Engine and ECT > Utility
        Tester Display
        All Readiness

      2. Input DTC P0724.

      3. Check that STATUS is NORMAL.

        Tech Tips


        • If STATUS is NORMAL, DTC judgment is complete and it can be determined that the system is normal.

        • If STATUS is INCOMPLETE or N/A, DTC judgment is incomplete. Perform the following procedure again 5 times: accelerate the vehicle to 30 km/h (19 mph) or more, depress the brake pedal and decelerate the vehicle to 3 km/h (1.8 mph) or less.

      Result
      Proceed to
      NEXT

    NEXT

    END

  7. REPLACE STOP LAMP SWITCH ASSEMBLY


    1. Replace the stop light switch assembly.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

    GO TO STEP 6 Click here