Possible causes

– Faulty Auto Shutdown (ASD) relay
– Auto Shutdown (ASD) relay harness is open or shorted
– Auto Shutdown (ASD) relay circuit poor electrical connection
– Faulty Engine Control Module (ECM)

Tech notes

Check all the Engine Control Module (ECM) fuses, if the fuses are OK try replacing the ASD relay.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P0685 MITSUBISHI Description

Short or open in Auto Shutdown (ASD) relay circuit