SFI SYSTEM (w/ Secondary Air Injection System), Diagnostic DTC:P0724

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

DESCRIPTION

The stop light switch assembly is a duplex system that transmits 2 signals: STP and ST1-. These 2 signals are used by the ECM to monitor whether or not the brake system is working properly.

DTC No. DTC Detection Condition Trouble Area
P0724 The stop light switch remains on even when the vehicle is driven in a 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 signal circuit

  • Stop light switch assembly

  • ECM

WIRING DIAGRAM

Refer to DTC P0504 Click here.

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. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

  • Read freeze frame data using the intelligent tester. 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, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

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 tester on.

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

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

      OK
      Brake Pedal Display
      Released OFF
      Depressed ON

    NG

    INSPECT STOP LIGHT SWITCH ASSEMBLY Click here

    OK

    CHECK FOR INTERMITTENT PROBLEMS

  2. INSPECT STOP LIGHT SWITCH ASSEMBLY


    1. Inspect the stop light switch assembly Click here.


    NG

    REPLACE STOP LIGHT SWITCH ASSEMBLY

    OK

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


    1. Disconnect the ECM connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      B7-4 (STP) - Body ground Brake pedal depressed 7.5 to 14 V
      B7-4 (STP) - Body ground Brake pedal released Below 1.5 V

    3. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - STOP LIGHT SWITCH ASSEMBLY)

    OK

    REPLACE ECM