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.
PCM sets DTC P0504 if the PCM detects signal of the brake warning lamp and brake switch do not correlate within the predetermined time.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Plausibility check between Brake Light Switch(BLS) and Brake Test Switch(BTS) | 1. Open or short circuit in harness 2. Poor connection or damaged harness 3. Faulty brake warning lamp or brake test switch |
Enable Conditions |
•
Engine running | |
Threshold Value |
•
Time between brake light switch and brake test switch do not correlate longer than > 10 sec | |
Diagnostic Time |
•
12 times brake pedal activation | |
MIL On Condition |
•
- |
Test Condition | Brake Test Switch | Brake Light Switch |
Step on brake pedal | Battery Voltage | Battery Voltage |
Release brake pedal | Approx. 0V | Approx. 0V |
