Code result
P04AC
EVAP System Purge Control Valve B Circuit Low
Moderate severity
What it means
Same as P04AB with the control line shorted to ground. The evaporative system captures fuel vapor from the tank and purges it into intake; leaks or stuck purge valves leak hydrocarbons and cause emissions failures.
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
Control line shorted to ground
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.
Harness chafing through insulation
lowLess common, but worth ruling out after the more likely causes.
Related help
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