Code result
P251B
PTO Enable Switch Circuit Low
Moderate severity
What it means
The PTO enable switch input reads stuck low — typically a short to ground or a permanently closed switch. The ECM either sees PTO enabled when the operator has not requested it, or cannot release the PTO mode after work.
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
Switch wire shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Switch stuck closed
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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