General Information

Engine Control
P0504 Brake Switch - General Information

Component Location





General Description

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 brake test or brake light) to memorize the abnormality when the signals of depressing and releasing the brake pedal are detected simultaneously.

DTC Description

ECM sets DTC P0504 if the ECM detects signal of the brake warning lamp and brake switch are not correlate within the predetermined time.

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data




1. Brake Test Switch
2. Brake Light Switch