P0504

DTC P0504 Brake Switch "A"/"B" Correlation

CIRCUIT DESCRIPTION

DTC Detecting Condition:

In this system, the signal of the stop light switch is used to judge whether the acceleration system is abnormal or not.

The stop light switch has a duplex system (signals STP and ST1-) to memorize the abnormality when the signals of depressing and releasing the brake pedal are detected simultaneously.

HINT: Normal condition is as shown in the table.

Wiring Diagram:

Step 1 - 2:

Step 3 - 4:

INSPECTION PROCEDURE

HINT: Read freeze frame data using hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, this is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.

CHECK FOR INTERMITTENT PROBLEMS

Hand-held tester only:
By putting the vehicle's ECM in the check mode, 1 trip detection logic is possible instead of 2 trip detection logic and sensitivity to detect open circuits is increased. This makes it easier to detect intermittent problems.
1. Clear the DTCs
2. Set the check mode
3. Perform a simulation test
4. Check the connector and terminal
5. Handle the connector