Code result
P0571
Cruise Control/Brake Switch A Circuit Malfunction
Moderate severity
What it means
The brake light switch signal seen by the ECU is implausible — for example, both contacts active simultaneously, or no signal change despite the brake pedal being pressed (cruise control engages and disengages on this signal). On many cars also disables shift interlock.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Brake switch failed (worn contacts, internal break)
highOne of the most commonly reported causes for this code — check this first.
Switch misadjusted (does not actuate at correct pedal position)
mediumA plausible cause — test and verify before replacing parts.
Related help
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