Evaporative Emission Control System Purge Control Valve Circuit Open
What does P0444 mean?
The P0444 code means the vehicle's onboard diagnostic system has detected: Evaporative Emission Control System Purge Control Valve Circuit Open. This is a low severity code.
Common Symptoms
- Check Engine Light illuminated
- Fuel vapor odor near the engine bay
- Slightly rough idle
- Failed emissions test
Probable Causes (Ranked by Likelihood)
- Open circuit in purge valve wiring harness Very High
- Failed purge control solenoid High
- Corroded or damaged connector at the purge valve Moderate
- Faulty ECM/PCM driver circuit Low
Step-by-Step Diagnostic Procedure
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Inspect the purge valve connector for corrosion, bent pins, or damage
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Use a multimeter to check for continuity in the purge valve wiring harness from ECM to the valve
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Measure resistance across the purge valve solenoid terminals -- typical range is 20-40 ohms
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Apply 12V directly to the purge valve to confirm it clicks and operates
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Check ECM connector pins for the purge valve driver circuit
Frequently Asked Questions
Can I drive with code P0444?
Yes. This code indicates an electrical issue with the purge valve circuit and does not affect engine performance or safety. It will cause an emissions test failure.
How do I test the purge valve solenoid?
Disconnect the electrical connector and measure resistance across the solenoid terminals with a multimeter. A reading of 20-40 ohms is typical. An open reading (OL) confirms a failed solenoid.
Could rodent damage cause P0444?
Yes. Rodents frequently chew through underhood wiring, and the purge valve harness is a common target. Inspect the wiring for chew marks or exposed copper.