Code result
C0509
Right Front Wheel Speed Sensor A Circuit High
High severity
What it means
Right-front WSS A signal voltage above expected range. Wheel-speed signals feed ABS, ESC, traction control, transmission and odometer — a single dropped signal disables all of these safety functions until repaired.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Signal wire open or short to power
highOne of the most commonly reported causes for this code — check this first.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Supply wire pinched against B+ source
lowLess common, but worth ruling out after the more likely causes.
Related help
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