Finally got that Cummins ISX to fire after 4 hours of diagnosing

I was on a job outside Birmingham last Tuesday and the ECM wouldn't talk to my laptop at all. Turned out to be a chafed wire behind the intake manifold grounding out the data link. Has anyone else had a bad ground cause a no-comm issue on these newer engines?

2 comments

2 Comments

casey94326d ago

Bad grounds will absolutely cause a no-comm on those ISX engines. Had a similar issue on a '19 model last month where the ground strap from the frame to the cab was corroded to hell. Traced it all the way down to find voltage dropping to almost nothing at the ECM connector. Took me two hours with a multimeter and a schematic to finally see it.

nathan_thompson6226d ago

Man I used to be one of those guys who always blamed the ECM first when a no-comm popped up. Thought it was almost always a computer failure or a bad sensor. But after chasing my tail on a few of these ISX trucks I gotta admit I was wrong. That ground strap corrosion thing is way more common than I ever gave it credit for. Now I always start with checking grounds before I even think about replacing a module. Saves a ton of headache and money when you just take that extra twenty minutes with a multimeter.