AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P0724

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

DESCRIPTION

The purpose of this circuit is to prevent the engine from stalling while driving in the lock-up condition when the brakes are suddenly applied.

When the brake pedal is depressed, this switch sends a signal to the TCM. Then the TCM cancels the operation of the lock-up clutch while braking is in progress.

DTC No. DTC Detection Condition Trouble Area
P0724

Both of following conditions are met:


  • Stop light switch remains ON even when vehicle is driven in GO (30 km/h (18.63 mph) or more) and STOP (less than 3 km/h (1.86 mph)) pattern 5 times

  • 2 trip detection logic

  • Stop light switch

  • Short in stop light switch signal circuit

  • Harness and connector

  • TCM

MONITOR DESCRIPTION

This DTC indicates that the stop light switch remains ON. When the stop light switch remains ON during GO and STOP driving, the TCM interprets this as a fault in the stop light switch. Then the MIL illuminates and the TCM stores the DTC. The vehicle must GO (30 km/h (18.63 mph) or more) and STOP (less than 3 km/h (1.86 mph)) 5 times for 2 driving cycles in order for the DTC to be output.

WIRING DIAGRAM

A01GNACE03

INSPECTION PROCEDURE

PROCEDURE


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


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the intelligent tester on.

    4. Enter the following menus: Powertrain / ECT / Data List / Stop Light Switch.

    5. Read the value displayed on the intelligent tester when the brake pedal is depressed and released.

      OK
      Tester Display Measurement Item/Range Normal Condition
      Stop Light Switch

      Stop light switch status/

      ON or OFF

      Brake pedal:


      • Depressed: ON

      • Released: OFF

    NG

    CHECK STOP LIGHT SWITCH INSTALLATION Click here

    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here

  2. CHECK STOP LIGHT SWITCH INSTALLATION


    1. Check the stop light switch assembly installation Click here.

      OK
      Stop light switch is installed correctly.

    NG

    SECURELY REINSTALL STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - TCM)


    1. Disconnect the A79 stop light switch connector.

    2. Disconnect the A12 TCM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A79-2 (L) - A12-2 (STP) Always Below 1 Ω
      A79-2 (L) - Body ground Always 10 kΩ or higher
      A12-2 (STP) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK STOP LIGHT SWITCH ASSEMBLY


    1. Check the stop light switch assembly Click here.


    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  5. REPLACE TCM


    1. Replace the TCM Click here.


    NEXT

    PERFORM A/T CODE REGISTRATION Click here