They all have 1 thing in common, they need constant power to operate continously. So I would first check your battery's state of charge, your alternator's output and the condition/connection of your battery cables and ground wires.
You're getting the check engine light because the engine's components are not getting the power it needs to operate properly.
You're getting partial power so there's no break in the wire harness but something is in the way
Sunday, June 20th, 2010 AT 2:34 AM