2AR-FE Engine Control
2AR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0724: Brake Switch "B" Circuit High
P0724 - Brake Switch "B" Circuit High
DESCRIPTION
The purpose of this circuit is to prevent the engine from stalling when brakes are suddenly applied while driving in lock-up condition.
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.
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, the MIL turns on and the ECM 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
TYPICAL ENABLING CONDITIONS
The stop light switch remains ON during STOP and GO 5 times.
GO and STOP are defined as follows:
TYPICAL MALFUNCTION THRESHOLDS
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation) [A].
4. Wait 5 seconds after clear DTCs.
5. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
6. Input the DTC: P0724.
7. Check the DTC judgment result [B].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or UNKNOWN, perform steps [C] through [E].
8. Start the engine [C].
9. Accelerate the vehicle to 30 km/h (19 mph) or more, depress the brake pedal and decelerate the vehicle to 3 km/h (1.8 mph) or less [D]. Repeat step [D] 5 times.
10. Check the DTC judgment result [E].
11. If the test result is UNKNOWN, enter the following menus: Powertrain / Engine and ECT / Trouble Code / Pending.
12. Read Pending DTCs.
HINT
If a pending DTC is output, the system is malfunctioning.
13. If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.
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 P0504.
INSPECTION PROCEDURE
HINT
Read freeze frame data using the Techstream. 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.
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
1. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Stop Light Switch.
(e) Read the values displayed on the Techstream.
OK:
NG -- INSPECT STOP LIGHT SWITCH
OK -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems
2. INSPECT STOP LIGHT SWITCH P0504
NG -- REPLACE STOP LIGHT SWITCH Removal
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - ECM)
(a) Disconnect the ECM connector.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
(d) Reconnect the ECM connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM Removal