Failed purge control solenoid valve with an open internal coil; Broken, corroded, or disconnected wire in the solenoid control circuit; Short to battery voltage on the control wire between the ECM and solenoid; Corroded or loose electrical connector at the purge solenoid; Faulty ECM driver circuit, though this is rare compared with wiring issues; Rodent damage to the harness near the intake manifold or canister; Water intrusion into the connector causing high resistance or an open circuit

DTC codes / Subaru codes / P1422

P1422 · SubaruEVAP Purge Control Solenoid Valve Circuit High Input

Q: What does code P1422 mean?

EVAP Purge Control Solenoid Valve Circuit High Input. P1422 on a Subaru means the engine control module (ECM) has detected an abnormally high voltage on the control circuit for the EVAP purge control solenoid valve, which is the component that meters fuel vapor from the charcoal canister into the intake. The ECM commands the solenoid on and off by grounding its control wire, and a high-voltage reading tells the module that the circuit is open, shorted to power, or that the solenoid coil has failed.

P1422 on a Subaru means the engine control module (ECM) has detected an abnormally high voltage on the control circuit for the EVAP purge control solenoid valve, which is the component that meters fuel vapor from the charcoal canister into the intake. The ECM commands the solenoid on and off by grounding its control wire, and a high-voltage reading tells the module that the circuit is open, shorted to power, or that the solenoid coil has failed.

SystemPowertrain

Code typeSubaru specific

SeverityLow

Fix difficultyIntermediate

AreaAuxiliary emission controls

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
A faint fuel or gasoline odor around the engine bay or near the charcoal canister
Slightly rough idle or a stumble just after refueling
Occasional difficulty refueling if the purge system is stuck closed
A pending P1422 that returns quickly after being cleared
No drivability change in most cases because the purge solenoid only affects vapor flow

Common causes, most likely first

Failed purge control solenoid valve with an open internal coil
Broken, corroded, or disconnected wire in the solenoid control circuit
Short to battery voltage on the control wire between the ECM and solenoid
Corroded or loose electrical connector at the purge solenoid
Faulty ECM driver circuit, though this is rare compared with wiring issues
Rodent damage to the harness near the intake manifold or canister
Water intrusion into the connector causing high resistance or an open circuit

How to diagnose and fix it

Clear the code and test-drive to confirm whether P1422 returns immediately or is intermittent
Inspect the purge solenoid connector and harness for corrosion, chafing, or rodent damage
Measure the resistance of the purge solenoid coil with a multimeter and compare to specification
Check for battery voltage on the control wire with the key on and the solenoid disconnected
Back-probe the ECM connector to verify the driver circuit is not shorted to power
Replace the purge control solenoid valve if the coil is open or the valve does not click when commanded
Repair or replace the affected section of harness and clear the code to verify the repair

What high input really means on a Subaru purge circuit

A high input code does not always mean the solenoid is bad; a disconnected or corroded connector will produce the same voltage reading because the ECM sees no ground path.
Subaru purge solenoids are pulse-width modulated, so a simple click test with 12 volts can damage the coil if applied continuously; use a duty-cycle tester or the scan tool activation instead.
The same P1422 can set from a short to power on the control wire, which is often caused by a pinched harness near the intake manifold rather than by the solenoid itself.
A stuck-open purge solenoid can cause a rough idle and fuel smell, but P1422 specifically indicates an electrical circuit fault, not a mechanical stuck valve.
After replacing the solenoid, check the EVAP canister for charcoal debris that can travel through the line and jam the new valve.

Can I keep driving with P1422?

You can usually continue driving with P1422 because the purge solenoid only affects fuel vapor flow and does not change engine performance or safety. Avoid topping off the fuel tank and have the circuit inspected soon, since a persistent fuel vapor leak can fail an emissions test.

Tools that help

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Guidance is general and written for Subaru vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.