How do you correct the P0685 code in a 2007 Honda Pilot

Question

Check engine light comes on

Answer 1

P0685 Power control module circuit /  internal / circuit malfunction

When this code set it is when the PCM does not shut down when the voltage to the PCM is turned off. Turning the ignition off , the PCM is still turned on. You can relate this to the PGM-FI main relay. Relay are not built like it once was. Honda are known to have sticking relays , such as for the A/C compressor. even with the off A/C off and the engine off, there a battery drain. As for the start to resolve P0685 replace the PGM-FI relay.