P0504

DTC P0504 BRAKE SWITCH "A"/"B" CORRELATION

CIRCUIT DESCRIPTION

DTC Detection Condition:

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

The stop lamp 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:

INSPECTION PROCEDURE

HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it 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.

Step 1 - 3:

Step 4:

Hand-held tester

Step 1 - 2:

Step 3 - 4:

OBD II scan tool (excluding hand-held tester)

CHECK FOR INTERMITTENT PROBLEMS

Hand held tester only:
By putting the vehicle's ECM in the check mode, the 1 trip detection logic is possible instead of the 2 trip detection logic, and the sensitivity to detect faults 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. Wiggle the harness and the connector.