P04AB
EVAP System Purge Control Valve B Circuit Open
The second EVAP purge control valve (B) - used on systems with a divided purge path or on twin-bank engines - shows an open control circuit. The ECU cannot drive the valve, so vapor cannot be purged through this stage; tank pressure may rise and emissions diagnostics fail.
The second EVAP purge control valve (B) - used on systems with a divided purge path or on twin-bank engines - shows an open control circuit. The ECU cannot drive the valve, so vapor cannot be purged through this stage; tank pressure may rise and emissions diagnostics fail.
Common causes
- high
Open in harness or connector
One of the most commonly reported causes for this code — check this first.
Typical part cost: $90-310
- medium
Solenoid winding open
A plausible cause — test and verify before replacing parts.
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 P04AB mean?
P04AB means "EVAP System Purge Control Valve B Circuit Open". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04AB?
open in harness or connector; solenoid winding open; pin pushed back out of connector body — 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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