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

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 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

  • 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

A015ZBIE03

INSPECTION PROCEDURE

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 engine switch off.

  3. Connect the intelligent tester to the DLC3.

  4. Turn the engine switch on (IG).

  5. Turn the intelligent tester on.

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

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

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

    Stop light switch status/

    ON or OFF

    Brake pedal is


    • ON: Depressed

    • OFF: Released

    		 -

PROCEDURE


  1. INSPECT STOP LIGHT SWITCH

    A01634ZE01

    1. Remove the stop light switch.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 - 2 Pin not pushed Below 1 Ω
      3 - 4 Pin pushed Below 1 Ω
      1 - 2 Pin pushed 10 kΩ or higher
      3 - 4 Pin not pushed 10 kΩ or higher

    NG

    REPLACE STOP LIGHT SWITCH

    OK

  2. CHECK STOP LIGHT SWITCH (POWER SOURCE)


    1. A015Z57E03

      Disconnect the stop light switch connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A22-2 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH - BATTERY)

    OK

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


    1. A0161TWE20

      Connect the stop light switch connector.

    2. Disconnect the TCM connector.

    3. Measure the voltage according to the value(s) in the table below when the brake pedal is depressed and released.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A58-23 (STP) - Body ground Brake pedal is depressed 11 to 14 V
      Brake pedal is released Below 1 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE TCM


    1. Replace the TCM Click here.


    NEXT

    PERFORM A/T CODE REGISTRATION Click here