GSIC - Global Service Information Center

### DTC P0724 Brake Switch "B" Circuit High

## for Preparation Click here

## 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 ECM. Then the ECM cancels the operation of the lock-up clutch while braking is in progress.

DTC No. | DTC Detection Condition | Trouble Area

P0724

Stop light switch remains ON even when vehicle is driven in STOP (less than 3 km/h (2 mph)) and GO (30 km/h (19 mph) or more) pattern 5 times (2 trip detection logic)

1. Short in stop light switch signal circuit
2. Stop light switch
3. ECM

## 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 ECM interprets this as a fault in the stop light switch. Then the MIL illuminates and the ECM 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 output.

## WIRING DIAGRAM

## INSPECTION PROCEDURE

1.READ VALUE OF DATA LIST (STP SIGNAL)

HINT:

  Using the intelligent tester's Data List allows switch, sensor, actuator and other item values to be read without removing any parts. Reading the Data List early in troubleshooting is one way to save time.

1. Warm up the engine.

1. Turn the ignition switch OFF.

1. Connect the intelligent tester to the DLC3.

1. Turn the ignition switch ON and push the tester main switch ON.

1. Enter the following menus: Powertrain / Engine and ECT / Data List.

1. Follow the instructions on the tester and read the Data List.

Item | Measurement Item/ Range (Display) | Normal Condition | Diagnostic Note

Stop Light Switch

Stop light switch status/
ON or OFF

1. Brake pedal is depressed: ON
2. Brake pedal is released: OFF

-

CAUTION:

  In the table above, 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.

| OK |

Go to step 3

NG |

2.INSPECT STOP LIGHT SWITCH

1. Remove the stop light switch.

1. Measure the resistance of the switch.

   Standard resistance:

     Tester Connection | Switch Condition | Specified Condition
     1 - 2 | Pin pushed (pedal released) | 10 kΩ or higher
     1 - 2 | Pin not pushed (pedal depressed) | Below 1 Ω
     3 - 4 | Pin pushed (pedal released) | 10 kΩ or higher
     3 - 4 | Pin not pushed (pedal depressed) | Below 1 Ω

| NG |

REPLACE STOP LIGHT SWITCH

OK |

3.CHECK WIRE HARNESS (ECM - BATTERY)

1. Measure the voltage of the wire harness side connector.

   Standard voltage:

     Tester Connection | Condition | Specified Condition
     E14-15 (STP) - Body ground | Brake pedal is depressed | 10 to 14 V
     E14-15 (STP) - Body ground | Brake pedal is released | Below 1 V

| NG |

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK |

REPLACE ECM