P04AD
EVAP System Purge Control Valve B Circuit High
Same as P04AB with the control line shorted to supply. 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.
Same as P04AB with the control line shorted to supply. 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.
Common causes
- high
Control line shorted to supply
One of the most commonly reported causes for this code — check this first.
Typical part cost: $90-310
- low
Connector pins corroded - high contact resistance
Less common, but worth ruling out after the more likely causes.
Typical part cost: $90-310
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P04AD mean?
P04AD means "EVAP System Purge Control Valve B Circuit High". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04AD?
control line shorted to supply; connector pins corroded - high contact resistance; supply wire pinched against b+ source — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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