DTC P0724 Brake Switch "B" Circuit High

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 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)	Short in stop light switch signal circuit Stop light switch ECM

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

Refer to DTC P0504 ().

INSPECTION PROCEDURE

HINT:

Using the GTS to read the 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.

NOTICE:

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.

Warm up the engine.

Turn the engine switch off.

Connect the GTS to the DLC3.

Turn the engine switch to ON.

Turn the GTS on.

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

Follow the instructions on the GTS and read the Data List.

Item	Measurement Item/ Range (Display)	Normal Condition	Diagnostic Note
STOP LIGHT SW (Stop Light Switch)	Stop light switch status/ ON or OFF	Brake pedal is depressed: ON Brake pedal is released: OFF	-

1.INSPECT STOP LIGHT SWITCH

Dtc P0724 Brake Switch B Circuit High. 3UR-FE ENGINE CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Remove the stop light switch.

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
Pin pushed 10 kΩ or higher
3 - 4 Pin not pushed 10 kΩ or higher
Pin pushed Below 1 Ω

NG

REPLACE STOP LIGHT SWITCH ()

OK

2.CHECK HARNESS AND CONNECTOR (ECM - BATTERY)

Disconnect the ECM connector.

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

Standard Voltage:
Tester Connection Condition Specified Condition
A38-36 (STP) - Body ground Brake pedal is depressed 11 to 14 V
A38-36 (STP) - Body ground Brake pedal is released Below 1 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

REPLACE ECM ()

3UR-FE ENGINE CONTROL

Land Cruiser URJ200 URJ202 GRJ200 VDJ200

SFI SYSTEM

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

Tester Connection	Condition	Specified Condition
A38-36 (STP) - Body ground	Brake pedal is depressed	11 to 14 V
A38-36 (STP) - Body ground	Brake pedal is released	Below 1 V