AUTOMATIC TRANSAXLE 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 when the brakes are suddenly applied while driving in lock-up.

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 Code DTC Detection Condition Trouble Area
P0724 The stop light switch remains on even when the vehicle is driven in a STOP (less than 3 km/h (2 mph)) and GO (30 km/h (19 mph) or more) pattern 5 times (2-trip detection logic).

  • Short in stop light switch signal circuit

  • Stop light switch

  • TCM

MONITOR DESCRIPTION

This DTC indicates that the stop light switch remains on. When the stop light switch remains on during "stop and go" driving, the TCM interprets this as a fault in the stop light switch, illuminates the MIL and stores the DTC. The vehicle must stop (less than 3 km/h (2 mph)) and go (30 km/h (19 mph) or more) five times for two consecutive driving cycles in order for this DTC to be stored.

WIRING DIAGRAM

A01IPO7E01

INSPECTION PROCEDURE


  1. DATA LIST

    Tech Tips

    Using the intelligent tester to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

    Note

    In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.


    1. Warm up the engine.

    2. Turn the ignition switch off.

    3. Connect the intelligent tester to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn the intelligent tester on.

    6. Enter the following menus: Powertrain / ECT / Data List.

    7. According to the display on the tester, read the Data List.

      ECT
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light Switch

      Stop light switch status/

      ON or OFF

      • ON: Brake pedal depressed

      • OFF: Brake pedal released

      		 -

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. 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

      • ON: Brake pedal depressed

      • OFF: Brake pedal released

    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 A55 stop light switch connector.

    2. Disconnect the C29 TCM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A55-3 (L) - C29-12 (STP) Always Below 1 Ω
      A55-3 (L) - Body ground Always 10 kΩ or higher
      C29-12 (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

    REPLACE TCM Click here