DTC P0504 Brake Switch "A" / "B" Correlation
DTC P0724 Brake Switch "B" Circuit High
DESCRIPTION
The stop light switch is 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. If the signals, which indicate the brake pedal is being depressed or released, are detected simultaneously, the ECM interprets this as a malfunction in the stop light switch and sets the DTC.
HINT: The normal conditions are as shown in the table below. The signals can be read using the intelligent tester.
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 and the MIL comes on and the ECM stores the DTC. The vehicle must stop (less than 2 mph (3 km/h)) and go (19 mph (30 km/h) or more) 5 times for two driving cycles in order to detect a malfunction.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT: Read freeze frame data using the intelligent tester. 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 CHECK OPERATION OF STOP LIGHT
OK: Stop lights turn on when brake pedal is depressed.
2 INSPECT STOP LIGHT SWITCH ASSEMBLY
Standard resistance
3 READ VALUE OF INTELLIGENT TESTER (STP SIGNAL AND ST1 - VOLTAGE)
Standard
Standard voltage
4 CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH - ECM)
Standard resistance : Check for open
Check for short
REPLACE ECM
Customer problem analysis
HINT:
In troubleshooting, confirm that the problem symptoms
have been accurately identified. Preconceptions should be
discarded in order to make an accurate judgment. To
clearly understand what the problem symptoms are, it is
extremely important to ask the customer about the
problem an ...
Reassembly
1. INSTALL NO. 1 SEAT CUSHION FRAME SUBASSEMBLY
Install the seat cushion frame with the bolt.
Torque: 20.6 N*m (210 kgf*cm, 15 ft.*lbf)
2. INSTALL RECLINING CONTROL LINK SUBASSEMBLY
Install the reclining control link with the E-ring.
Install the nut.
3. INSTALL RE ...
Initialization
1. ZERO POINT CALIBRATION
NOTICE:
Make sure that the front passenger seat is not
occupied before performing the operation.
HINT:
Perform the zero point calibration and sensitivity check if
any of the following conditions occur.
The occupant classification ECU is replaced.
Acc ...