Code result
P25BF
Alternative Fuel Disable Control Circuit High
Moderate severity
What it means
Voltage on the alternative-fuel disable control line is above the expected window. Often a short to battery upstream of the relay or a stuck-on driver in the control module.
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
Disable control wire shorted to a B+ supply
highOne of the most commonly reported causes for this code — check this first.
Output driver stuck on inside the control module
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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