P0504
Low severityBrake Switch Correlation
The brake light switch signals are inconsistent. This can prevent cruise control from working and may cause transmission shifting issues or warning lights.
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Common causes of P0504
1Faulty brake light switch
2Misadjusted brake pedal switch
3Damaged switch plunger
+2 more causes
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Diagnose P0504 freeCommonly affected vehicles
VolkswagenAudiFordVauxhallRenault
P0504 can appear on any vehicle — these are the makes where it is most frequently reported.
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