Dtc P0724 Brake Switch B Circuit High
DESCRIPTION
MONITOR DESCRIPTION
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
CONFIRMATION DRIVING PATTERN
WIRING DIAGRAM
INSPECTION PROCEDURE
READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)
INSPECT STOP LIGHT SWITCH
CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - ECM)
DTC P0724 Brake Switch "B" Circuit High |
DESCRIPTION
The stop light switch 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
| Stop light switch remains ON even when vehicle repeats 5 cycles of STOP (less than 1.86 mph [3 km/h]) and GO (18.65 mph [30 km/h] or more) (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 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.
MONITOR STRATEGY
Related DTCs
| P0724: Stop light switch verify switch input
|
Required Sensors/Components (Main)
| Stop light switch
|
Required Sensors/Components (Related)
| Speed sensor
|
Frequency of Operation
| Continuous
|
Duration
| 5 times
|
MIL Operation
| 2 driving cycles
|
Sequence of Operation
| None
|
TYPICAL ENABLING CONDITIONS
Monitor runs whenever following DTCs not present
| None
|
Battery voltage
| 8 V or more
|
Ignition switch
| ON
|
Starter
| Off
|
GO: Vehicle speed
| 18.65 mph (30 km/h) or more
|
STOP: Vehicle speed
| Less than 1.86 mph (3 km/h)
|
TYPICAL MALFUNCTION THRESHOLDS
Brake pedal position switch
| On stuck
|
CONFIRMATION DRIVING PATTERN

- Connect the Techstream to the DLC3.
- Turn the ignition switch to ON and turn the Techstream on.
- Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation) (COROLLA_ZRE142 RM000000PDK0ZAX.html).
- Turn the ignition switch off and wait for at least 30 seconds.
- Turn the ignition switch to ON and turn the Techstream on [A].
- Wait 5 seconds.
- Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [B].
- Read the pending DTCs.
- HINT:
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
- Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
- Input the DTC: P0724.
- Check the DTC judgment result.
Techstream Display
| Description
|
NORMAL
| - DTC judgment completed
- System normal
|
ABNORMAL
| - DTC judgment completed
- System abnormal
|
INCOMPLETE
| - DTC judgment not completed
- Perform driving pattern after confirming DTC enabling conditions
|
N/A
| - Unable to perform DTC judgment
- Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
|
- HINT:
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or N/A, perform steps [C] through [E].
- Start the engine [C].
- Accelerate the vehicle to 19 mph (30 km/h) or more, and then depress the brake pedal and decelerate the vehicle to 1.8 mph (3 km/h) or less [D]. Repeat step [D] 5 times.
- CAUTION:
- When performing the confirmation driving pattern, obey all speed limits and traffic laws.
- Check the DTC judgment result [E].
- If no pending DTC is output, perform a universal trip and check for permanent DTCs (COROLLA_ZRE142 RM000000PDK0ZAX.html).
- HINT:
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
Refer to DTC P0504 (Link).
INSPECTION PROCEDURE
- HINT:
- Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
1.READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH) |
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Stop Light Switch.
Read the values displayed on the Techstream.
- Result:
Item
| Measurement Item: Range (display)
| Normal Condition
|
Stop Light Switch
| Stop light switch status: ON or OFF
| - ON: Brake pedal is depressed
- OFF: Brake pedal is released
|
2.INSPECT STOP LIGHT SWITCH |
Inspect the stop light switch (COROLLA_ZRE142 RM0000014D9026X.html).
3.CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - ECM) |
Disconnect the ECM connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection
| Condition
| Specified Condition
|
A50-36 (STP) - Body ground
| Brake pedal released
| Below 1.5 V
|
Brake pedal depressed
| 7.5 to 14 V
|
Reconnect the ECM connector.
| REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LIGHT SWITCH - ECM) |
|
|