Powertrain
generic / SAE
P0504
Brake Switch "A"/"B" Correlation
Modern vehicles use two redundant brake switch signals (often one normally-open and one normally-closed). When the two signals disagree, this code is set; common causes include a misadjusted switch, internal switch failure, or wiring fault.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number5 / 04
Possible causes
- Brake switch misadjusted high
- Brake switch internal fault medium
Inspection / repair
- Difficulty: easy
- DIY: possible
- Estimated cost: 30–200 €
- Estimated time: 0.2–1 h
- Component: brake light switch
- Component: brake switch wiring
- MIL / check engine light
Sources
References
sae:J2012