P0504 means the two internal circuits of the brake light switch do not agree. Modern brake switches send two signals to the ECU for safety: one that closes when the pedal is pressed and one that opens. If the ECU sees both circuits in the same state at the same time, it sets P0504. The fix is almost always a new brake switch, sometimes combined with a pedal position adjustment.
DTC/P0504·Volkswagen
P0504 on Volkswagen: Causes, Symptoms and Fix Cost
Quick Answer
Moderate SeverityNot safe to driveVolkswagen
P0504 on a Volkswagen means the two internal circuits of the brake light switch do not agree. Modern brake switches send two signals to the ECU for safety: one that closes when the pedal is pressed and one that opens. If the ECU sees both circuits in the same state at the same time, it sets P0504. The fix is almost always a new brake switch, sometimes combined with a pedal position adjustment.
Repair cost on Volkswagen€23 - €173
What does P0504 mean on a Volkswagen?
Volkswagen Golf
2003-2024Mk6 and Mk7 Golf are covered by a 2014 VW recall for brake light switch failures that produce P0504 and erratic brake lights. The recall replacement is free of charge at VW dealers if not already done. Check the recall status by VIN before buying a switch from an aftermarket supplier.
What causes P0504 on a Volkswagen?
Beyond the generic causes listed on the main P0504 page, these are the Volkswagen-specific patterns we see most often:
Volkswagen GolfRecalled brake light switch on Mk6/Mk7 (2014 VW recall)
Volkswagen GolfPedal sensor misalignment after clutch master cylinder replacement
How to diagnose P0504 on a Volkswagen with OBD2
Follow these steps to pinpoint the root cause of P0504:
- Use a scan tool to view live brake switch data. Most ECUs show two signals (BLS and BTS or similar). Press the pedal and verify both change state cleanly together
- Inspect the pedal at rest. The switch plunger should be fully extended and resting against the pedal stop with no preload. A loose stop pad lets the pedal sit too low and pre-presses the switch
- Remove the connector and inspect for bent pins or corrosion. Reseat firmly and recheck
- If both signals stay correlated only when the connector is wiggled, repair the wiring. Otherwise, replace the brake switch as a unit
- Clear codes, perform any required relearn for cruise control, and confirm the brake lights work both at rest and when the pedal is pressed
How much does P0504 cost to fix on a Volkswagen? (EUR)
Estimated repair costs on a Volkswagen (Volkswagen parts and labour typically run 15% above the average for this code).
Prices estimated as of May 2026. Costs vary by region, vehicle, and shop.
Related codes that often appear with P0504 on Volkswagen
These codes commonly cluster with P0504 on Volkswagen vehicles:
P0571P0572P0573P0703U0140
FAQ: P0504 on Volkswagen
Why won't my car start after the brake light switch failed?
Push-button start vehicles require the brake pedal to be pressed before the engine will crank. The ECU checks the brake switch signal to confirm the pedal is depressed. If P0504 is set, the ECU cannot trust that signal and refuses to start as a safety measure.
Can I just replace the brake light switch myself?
On most cars yes. The switch is a small plastic part that twists or clips into a bracket above the brake pedal. The job typically takes 10 to 15 minutes and requires no special tools. Just disconnect the battery before unplugging the switch to avoid airbag warnings.
Why are my brake lights stuck on all the time?
A stuck-on circuit inside a failing brake switch is one of the classic P0504 symptoms. The pedal-released contact has welded closed, so the brake lights stay on even with the pedal up. Replace the switch to fix.
Will a recalled brake switch cause P0504?
Yes. VW issued a 2014 recall covering brake light switches on certain Golf, Polo, and Audi models because the internal contacts could disagree, triggering P0504 and causing erratic brake light behaviour. Check the recall status with your VIN before paying for parts.
Looking for the full P0504 reference (all makes, full diagnosis flow, complete repair cost matrix)?
See the main P0504 guideSkanyx · Volkswagen
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