Dtc P0724 Brake Switch B Circuit High

Engine Hybrid System. Land Cruiser. Urj200, 202 Grj200 Vdj200
1Gr-Fe Engine Control. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

MONITOR DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING GTS (STOP LIGHT SWITCH)

CHECK STOP LIGHT SWITCH ASSEMBLY INSTALLATION

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

CHECK STOP LIGHT SWITCH ASSEMBLY

DTC P0724 Brake Switch "B" Circuit High


DESCRIPTION

The stop light switch assembly is part of a duplex system that transmits two signals: STP and ST1-. These two signals are used by the ECM to monitor whether or not the brake system is working properly. This DTC indicates that the stop light switch assembly remains on. When the stop light switch assembly remains on during "STOP and GO" driving, the ECM interprets this as a fault in the stop light switch assembly. Then the ECM illuminates the MIL and stores the DTC.

DTC No.
DTC Detection Condition
Trouble Area
P0724
The stop light switch assembly remains on even when the vehicle repeats 5 cycles of STOP (less than 3 km/h [1.86 mph]) and GO (30 km/h [18.65 mph] or more) (2 trip detection logic).
  1. Short in stop light switch signal circuit
  2. Stop light switch assembly
  3. ECM

MONITOR DESCRIPTION

This DTC indicates that the stop light switch assembly remains on. When the stop light switch assembly remains on during "STOP and GO" driving, the ECM interprets this as a fault in the stop light switch assembly. The ECM turns on MIL and stores the DTC. The vehicle must STOP (less than 3 km/h (1.86 mph)) and GO (30 km/h (18.65 mph) or more) 5 times during 2 driving cycles, in order to detect a malfunction.

WIRING DIAGRAM

Refer to DTC P0504 (Click here).

INSPECTION PROCEDURE

HINT:
  1. Using the GTS, the Data List item "Stop Light Switch" and "ST1" can be read (Click here).
  2. Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.
1.READ VALUE USING GTS (STOP LIGHT SWITCH)

  1. Connect the GTS to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the GTS on.

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

  1. Read the value displayed on the GTS when the brake pedal is depressed and released.

    OK:

    Item
    		Measurement Item/Range
    		Normal Condition
    Stop Light Switch
    		Stop light switch assembly status/
    ON or OFF
    1. ON: Brake pedal depressed
    2. OFF: Brake pedal released


NG
Go to step 2
OK

CHECK FOR INTERMITTENT PROBLEMS (Click here)

2.CHECK STOP LIGHT SWITCH ASSEMBLY INSTALLATION

  1. Check the stop light switch assembly installation (Click here).

    OK:
    Stop light switch assembly is installed correctly.


NG
SECURELY REINSTALL STOP LIGHT SWITCH ASSEMBLY (Click here)
OK


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

  1. Disconnect the stop light switch assembly connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance:

    for LHD
    Tester Connection
    		Condition
    		Specified Condition
    A73-2 (L) - A38-36 (STP)
    		Always
    		Below 1 Ω
    A73-2 (L) or A38-36 (STP) - Body ground
    		Always
    		10 kΩ or higher

    for RHD
    Tester Connection
    		Condition
    		Specified Condition
    A73-2 (L) - A52-36 (STP)
    		Always
    		Below 1 Ω
    A73-2 (L) or A52-36 (STP) - Body ground
    		Always
    		10 kΩ or higher


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


4.CHECK STOP LIGHT SWITCH ASSEMBLY

  1. Check the stop light switch assembly (Click here).



NG
REPLACE STOP LIGHT SWITCH ASSEMBLY (Click here)
OK

REPLACE ECM (Click here)