General Information

Engine Control
P0504 Brake Switch - General Information

Component Location





General Description

The Stop lamp switch signal is used for the Cruise Control, ABS-ESC, Shifter release as well as brake lights. The stop lamp switch consists of two separate switches. One switch is open while the other switch is closed. When the brake pedal is not depressed, one circuit is system voltage while the other circuit is zero volts. When the brake pedal is depressed, the values of the two circuits are reversed. The PCM monitors the two signals. If both switches have the same value it will set the code.

DTC Description

The PCM monitors signals from both Stop lamp switches. If both switches have High or Low voltage simultaneously, (more than 0.5 sec) the PCM sets a P0504 DTC.

DTC Detecting Condition





Specification





Diagnostic Circuit Diagram





Signal Waveform & Data




Fig.1) Normal data of Brake Switch during brake pedal released after depressed.