Cascadia shut off randomly and turns back on while driving on the road

[JimT]

So, forgive me if I repeat something already mentioned, I only skimmed a few of the posts.

While the fuel pump is a high priority to address, I don't think it has anything to do with your original issue.

I've experienced something similar to what you described and I have a friend with a freightliner that had the same experience. Most likely it's one of 2 problems:

- Bad or broken battery cables.

My experience was a broken battery cable that would short out inside my aluminum battery box. Same symptoms, usually hit a bump just the right way an I'd lose power briefly like the key was shut off then it would come right back to life. Check all your connections and battery cables.

- There's some kind of power distribution module in the freightliner that likes to go bad.

I'm recalling what my friend told me, so maybe someone else can chime in with details. Basically takes the power from the battery and splits it off for the different systems. They go bad and intermittently lose power. I *think* it's located in the engine compartment, driver side on the firewall and from what my friend said it can be a pain to reach.

Otherwise, if it's neither of those it could also be a bad fuse or maybe even a bad ground wire. Finally, though not likely, the ECM could be going bad. It's hard to reach on a cm2250 so trying to tap it might be a challenge. I'd focus on the first two wiring issues though, as that's almost certainly where the problem lies.