DTC P1421 (EGRSOL_HI): EXHAUST GAS RECIRCULATION CIRCUIT HIGH INPUT Subaru Forester SF

Note. If vehicle is 2.2L Legacy equipped with manual transmission, check A/T-M/T identification circuit.

1. Turn ignition on. Using voltmeter connected to ground, backprobe PCM connector terminal No. 71. See appropriate wiring diagram in WIRING DIAGRAMS article in this section. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, check for poor connection in PCM connector. Repair as necessary. If connection is okay, replace PCM.
2. Turn ignition off. Disconnect EGR solenoid valve connector. Turn ignition on. Backprobe PCM connector terminal 71. If voltage is more than 10 volts, repair short in harness between PCM and EGR solenoid valve connector, then replace PCM. If voltage is 10 volts or less, go to next step.
3. Turn ignition off. Check resistance of EGR solenoid valve connector between terminals No. 1 and 2. If resistance is one ohm or less, replace EGR solenoid valve and PCM. If resistance is more than one ohm, check for poor connection in PCM connector. Repair as necessary. If connection is good, replace PCM.