Code result
P051D
Crankcase Pressure Sensor A Circuit High
Moderate severity
What it means
Same as P051A with the signal voltage above the plausible range. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
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
Signal shorted to supply
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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