DTC P1423 (VCMSOL_Hi): Evaporative Emission Control System Vent Control Circuit High Input

NOTE: Impreza 2.2L and Legacy models are equipped with a drain valve which may also be referred to as a vent control solenoid. They perform the same function.

Turn ignition on. Using voltmeter connected to ground, backprobe PCM connector terminal No. 35 (Brown/Yellow wire). If voltage reading is more than 10 volts, go to next step. If voltage reading is 10 volts or less, check for poor contact in PCM connector. Repair as necessary. If connection is okay, replace PCM.
Turn ignition off. Disconnect vent control solenoid valve connector. Turn ignition on. Using voltmeter connected to ground, backprobe PCM connector terminal No. 35 (Brown/Yellow wire). If voltage is more than 10 volts, repair short in wiring between PCM and vent control solenoid connector, then replace PCM. If voltage reading is 10 volts or less, go to next step.
Turn ignition off. Check resistance of purge control solenoid between terminals No. 1 and 2. If resistance is one ohm or less, replace vent control solenoid and PCM. If resistance is more than one ohm, check for poor contact in PCM connector. Repair as necessary. If connection is okay, replace PCM.