So I was driving down the road at about 60 when the rpm's dropped and the check engine light flickered and the car just shut off. .... I coasted to the shoulder and attempted to restart it. It won't crank and when the key is turned to on position the check engine light doesn't come on with the rest of them. I know the battery, starter, fuses and alternator are all good. I also thought it may have been the main relay so I replaced it but nada. Any idea what would cause the issue I'm having? Any help would be greatly appreciated.

If the engine light doesn't illuminate then odds are the ECM isn't getting power and you do have a blown fuse somewhere, not cranking or cranking and not starting?

When I turn the key.... It doesn't crank and at all. You expect to hear the starter turning the flywheel but nothing.

Does the car have an alarm?
Check the battery cables for good clean connection to the terminals and the terminals to good clean connections to the battery.

>

It had an alarm at one point in time but I removed it because it was poorly installed, plus wires were hanging everywhere... I used my multimeter to check for voltage and I'm getting between 11.96-12.15 when I test the grounds

If you're seeing voltage drops that bad between the negative post and the case of the starter then it's very likely that there's a bad ground between the battery and starter, run a jumper cable from the negative post to the starter case ear/bolt and see if it'll crank.

>

Yeah at this point I'm checking everything.... Who knows what the DIY electrician did to that car....