2010 Peter 389 dash glitching

[Billcummins6]

Morning,
I have a 2010 Petertbilt 389 with a Cummins 871 in it. My dash glitches, gauges will reset as I'm driving down the road. Its almost like cycling the key on. The cruise and Jakes will sometimes shut off if it gets real bad. It seems to do it while goin down a hill coasting, not while I'm under power. I've replaced the ECM twice, body controller and engine wiring harness..
Yesterday I hit a decent sized pot whole on the 40 in Flagstaff and the truck shut off on me. After I got stopped and checked everything out, it restarted like after a service (sounded fuel deprived) and ran smooth. It threw a code for a key off and low fuel rail pressure. I stored and cleared the codes and its been fine for the last 100 miles.. I have a good video of if i can figure out how to post it. Fuckin trucks, totally frustrated...

[Bengy88]

Pete’s give a lot of issues at the cab connectors. Try wiggling the wires while the truck is idling and see if there are any hiccups, check all of your grounds, and smack the shi#t out of the top of your ecm with a rubber hammer to see if it stumbles or shuts off.

[Billcummins6]

(04-24-2023 )Bengy88 Wrote:  Pete’s give a lot of issues at the cab connectors. Try wiggling the wires while the truck is idling and see if there are any hiccups, check all of your grounds, and smack the shi#t out of the top of your ecm with a rubber hammer to see if it stumbles or shuts off.

What panel do I have to remove to get to the body control wiring?

[Bengy88]

On 389s the connector is behind the kick panel on the drivers side and go through the firewall on the drivers side. There will be 2 square connectors with around 20 wires each on the firewall. They should have a bolt through the center of them and one should be over the top of the other.

[Rawze]

Tarnished fuses in the fuse panel can cause those issues too. Just because they are not blown does not mean they cannot make some slight resistance and cause ghost problems with the dash and buttons, etc. - Replace all of the old fuses with new ones in the panel.

Check that the alternator is not really noisy electrically, and that all battery terminals are clean and not tarnished too.

Check the grounds at the engine block beside the starter, they will corrode thru and cause noise and random voltage issues too.

[Billcummins6]

I found a bad ground wire my ECM Power connector. Thanks for all your help guys.