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 lock-up 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. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0724 Brake Switch "B" Circuit High 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 assembly

  • TCM

 Comes on DTC stored

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. Then the MIL illuminates and the TCM stores the DTC. The vehicle must stop (less than 3 km/h (2 mph)) and go (30 km/h (19 mph) or more) 5 times for 2 driving cycles in order for the DTC to be stored.

WIRING DIAGRAM

A01LCLDE01
*a FL MAIN
*b STOP
*c Stop Light Switch Assembly
*d Battery

CAUTION / NOTICE / HINT

Note

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

Tech Tips

After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


  1. Repeat below procedure for 5 times:*1


    • Stop the vehicle (vehicle speed is 3 km/h (2 mph) or less)

    • Drive the vehicle (vehicle speed is 30 km/h (19 mph) or more)

  2. Turn the ignition switch off.

  3. Perform step (*1) again.

  4. Check for DTCs again.

    Click here


  1. DATA LIST

    Tech Tips

    Using the GTS 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 GTS to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn the GTS on.

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

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


      Powertrain > ECT > Data List
      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

      		 -

      Powertrain > ECT > Data List
      Tester Display
      Stop Light Switch

PROCEDURE


  1. INSPECT STOP LIGHT SWITCH ASSEMBLY


    1. A01L99TC06
      *1 Pin
      *a

      Component without harness connected

      (Stop Light Switch Assembly)
      *b Not pushed
      *c Pushed

      Remove the stop light switch assembly.

      Click here

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      1 - 2

      Pin pushed

      (pedal released)

      		 10 kΩ or higher
      3 - 4

      Pin not pushed

      (pedal depressed)

      		 10 kΩ or higher
      1 - 2

      Pin not pushed

      (pedal depressed)

      		 Below 1 Ω
      3 - 4

      Pin pushed

      (pedal released)

      		 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (TCM - BATTERY)


    1. A01LBZTC11
      *a

      Rear view of wire harness connector

      (to TCM)

      Disconnect the TCM connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      G90-14 (STP) - Body ground Brake pedal depressed 11 to 14 V
      G90-14 (STP) - Body ground Brake pedal released Below 1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE TCM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR