579 inverter question

Yeah its super dirty, I cleaned it up some and my truck started.
I bought a 150 amp at peterbilt.
So if it doesn't start tomorrow, I'll replace it.
The truck is temperamental , sometimes it starts in one go and sometimes in 10 trys.
I hope it's just the connection.
But when I go to crank it, the power cuts off sometimes.
There could be a short somewhere in the starting circuit.
Or Maybe the connections not tight enough on that fuse. Have to tighten it. It's just that it's located in a pain in the ### spot.
And the bolts for the roof of the battery box are rusted and won't come lose so I have to break them off.

 

Check the connection clean or replace connectors of the alternator to starter and then continue to the batteries . Check if you can for continuity with a multimeter.
If you don't just inspect all Jumper's and battery connections . It could be as simply be a jumper causing the issue. These is the frist thing I would do if it was me and the cheapest .
Hope this helps you.

 

I cleaned the connections at the Mega fuse.
When I have time I will cleaner it thoroughly.
My truck starts now. But..
Lol I have bigger problems. Fcan data bus fail. There's a data link problem.
I do the on , off on , off trick and the truck turns on. But I'm sure there's a busted wire. Never mind I found it. Well one spot. There has been some patch work on the wire that i think is connected to what appears to be the cecu.
There's something else that's odd.
There's something dangling losely , it looks like a fuse box.

 

And before I forget great thanks for your help.
The dangling thing. Would you know what it is?

 

Glad you found the issue with the starting problem and by the way that second pic I haven't seen it before but I'll do some detective work. And see what I can find out for you if you can send me a picture of the top. it does look like some kind of relay box or fuse box

 

Hard to reach place. I'm gonna tie it down with a ziptie so it doesn't dangle aimlessly when I drive.
I gotta cut upon the wire with electrical tape I'm pretty sure there's some wire wear on some of those wires that's causing a short circuit.
Truck is just weird. Sometimes it starts, sometimes it doesn't start, sometimes the power is killed as I crank, sometimes it cranks and the interrupter relay kicks in a kills the power and sometimes it just starts up right away.
It went two months with no problem but as soon as I got into Louisiana and their bumpy roads, I started to experience this stuff once again.
Took it to a shop and they thought it was the battery disconnect lmfao!
I'm like my battery disconnect works fine.
It shuts off my power when I turn the thing off and it turns it back on.
It's a wiring issue. And I'm just gonna have to bust out the multimeter and check the omhs. It's gonna be a pain.

 

Found this dangling on the other side. This was more accessible.