Truck won't start

I'll give ya'll some really good advice:

ECMs rarely fail. 98% of the time its not the ECM. Pretty much every troubleshooting procedure in existance lists "Replace ECM" as the final step.

I've gone to a few electronics courses thru my employer and the number of ECMs replaced under warranty that were found to be fine was like 80% IIRC. Problem is people don't understand how they work, so they just point their finger there first.

 

Last year I tried to start my truck when the display was showing 10.8V, it cranked slow but it started. It run like 30 seconds and it shut off, tried restarting and nothing. The dashboard was showing a bunch of codes relating to comunication issues from different units. Checked everything I could think of, second day I swapped ecm from another truck and fired right up. It cost me 2K to learn bo to try starting the truck with low voltage. Needless to say now I keep it hooked up to a charger when parked.

It was a 2011 Volvo D13.

 

2005 m2 freightliner wont start batery charged replaced startermotor and motor turn over will not fire took ecm to freightliner del checked out ok maybe i need a ecm wiring harness is there a way to check this system?

 

Not that it matters, but you said a battery was missing, and added one. My Truck only has 3 batteries. Im guessing you already had a 4 battery harness, because you cleaned it up, Otherwise you would have to buy a new one, or add a short pos& neg cables. A good charge, while they’re all hooked together might take a while. Should disconnect positive from battery, to avoid blowing fuse. They recommend it anyway.

 

I think a good charge and good prime, with a good shot of ether, about 7 seconds worth, right before you crank it should do it.

 

Those compucheck fittings, are for pressuring system. The Truckstops have a pump of some type, to hook up to it. Mine doesn’t have one. A air blowgun and a rag, blowing pressure into tank, will push it up the pick up tube, while cranking it.Good Utube videos on this.