POS08Nox

Looking for help. 2008 Equinox Sport, 3.6L AWD. Pull out to go to work a week ago, all good until a 1/4 mile down the road it just shuts off without any warning at all. Will not crank or anything. Push the POS home and start looking into it. Checked all fuses and swapped a few relays around with no luck. When I turn the key on I dont hear the fuel pump at all and a bunch of warning messages are on the dash such as Service Vehicle Soon, Service Airbag, Service Stabilitrak, and Service Traction Control. Battery is good, charged it up with a trickle charger, its only a year old. Have 12v at the fuse box, lights and chimes inside all seem to work normal. When I turn the key to "start" all I get is a faint rapid clicking sound coming from the "Crank" relay in the underhood fuse box and the check engine light is rapidly flashing. Tried a new ECM that I ordered online and programmed using my VIN, didnt help anything, same exact issues.

I'm stuck, at 146k miles I might need to junk this headache. Any ideas or items to look at and check?

ruley73

I definitely wouldn't have replaced the ECM until I did my due diligence to confirm it was bad. Computers really don't fail very often, and are expensive to replace. You can try scanning for DTCs, but I suspect most are erroneous and won't provide much guidance. Your symptoms seem to indicate a bad main power or ground connection somewhere. I'd first look at the terminals on the starter solenoid. The alternator is usually connected to the rest of the electrical system at the starter solenoid so I'd look there first. If the terminals there are green and crusty that's very likely the problem.

POS08Nox

So the reason I went with swapping out the ECM first was because 4 years ago I had a very similar issue happen. Cruising down the highway at 70, Equinox just dies and wont crank, tons of messages on the dash same are with now. Got it towed home and after tons of looking I had a mechanic friend suggest grounding my ECM. I ran a small wire from the body of the ECM to a good ground point on in the engine bay. Started right up and ran fine for the last 4 years. So I figured that the ECM finally just took a crap because the symptoms were all the same as last time.

The starter is almost impossible to access on this Sport model. I didn't see any corroded wires or anything on it but its tucked in soo deep. I just need to keep looking I guess. I'm about to buy the schematics so I can start chasing wires down.

POS08Nox

Just an update, swapped out the ECM and it turned out to be the problem. Oddly enough about a week of driving and my alternator went out. Swapped that out to and back up and running.