Brake switch A circuit on Ford — cruise/start-stop drops and brake-light fault from the dual-stage brake switch on Focus/Fiesta/Mondeo.
Ford P0571 — Brake switch A circuit on Ford — cruise/start-stop drops and brake-light fault from the dual-stage brake switch on Focus/Fiesta/Mondeo. Typical UK independent garage cost: £25–£90.
What actually causes P0571 on a Ford
Ford's redundant brake switch fails on one of its two channels — cruise drops out, start-stop disables, sometimes the engine refuses to start (foot-on-brake check fails). £18 switch, 10-minute fit.
Ford engines that log P0571
- Focus Mk3/Mk4
- Fiesta Mk7/Mk8
- Mondeo Mk4/Mk5
- Kuga Mk1/Mk2
How we diagnose P0571 on a Ford
- Pull P0571 / P0703 / P0504 codes
- Operate brake pedal and watch both channels in live data
- Replace dual-stage switch — adjust per Ford procedure
- Clear codes and confirm cruise re-engages
The common misdiagnosis to avoid
Genuinely cheap fix that is often quoted as a £400+ pedal box job by uninformed garages. Always start with the switch.
Ford P0571 repair cost in the UK
Expect £25–£90 including parts and labour at an independent garage. Main-dealer quotes on Ford are usually higher for the same job, and the spread exists because the cheap cause and the expensive cause throw the same code — pay for the diagnosis before you pay for parts.
Bob's workshop tip
Ford P0571 = brake switch, full stop. Carry one in the van — you'll fit one a week.
Codes usually seen alongside P0571 on Ford
- P0504
- P0703
Symptoms drivers report with P0571
- Cruise control flat-out refuses to engage on the motorway.
- The 'ESP' or Traction Control warning light stays on the dash.
- Brake lights are either stuck on permanently or won't light up at all.
- Automatic gearbox won't let you shift out of 'Park' without a fight.
- Engine feels like it's 'cutting out' or hesitant when you're just cruising.
Repairs that clear P0571
- Brake switch replacement
For the generic, all-makes explanation of this code — meaning, every known cause and UK cost bands — see our P0571 guide.
Reading P0571 on a Ford properly
A generic reader will show P0571 and nothing else. What matters is the freeze-frame data stored with it — engine speed, load, coolant temperature and fuel trims at the moment the fault was logged — plus whether any other module on the Ford has logged something at the same time. Codes rarely arrive alone, and the order they were stored in usually points at which one is the cause and which are the consequences.
Clearing P0571 without fixing it
Erasing the code resets the Ford's readiness monitors as well as the light. The fault returns on the next drive cycle if the cause is still there, and in the meantime the incomplete monitors can stop the car passing an emissions check. After a genuine repair, the car is driven until the relevant monitor completes before it is handed back.
Bob's Mechanical Repairs is an independent garage in Birnam, Dunkeld, Perthshire, with 32 years of Bob's experience on the tools. If P0571 is showing on your Ford, bring any scan results with you — we will read the live data ourselves, confirm which cause it actually is, and price the repair before any work starts.