Threaded Mode | Linear Mode

09Pete386

Power Supply Lost With Ignition On - Data
Erratic. Intermittent. or Incorrect
Got this from a dealer, already on my 3rd Ecm still worth the same issue truck keeps turning off like someone turn the key off sometime it would start sometimes it wouldn’t, any ideas, some people say it’s electrical, not sure where to start and dealer as usually wants an arm an a leg and I’m already $5k in this.

hookliftpete

If you havent already, Id check all grounds and battery cables, as well as corrosion you cannot see under wire jackets.

09Pete386

(04-05-2022 )hookliftpete Wrote: If you havent already, Id check all grounds and battery cables, as well as corrosion you cannot see under wire jackets.

Thanks ye I checked mostly all my battery cables positive and grounds
Btw it’s and 09 peterbilt 386 isx15 if that helps.

Rawze

That is a pretty common issue with CM871's (a 2009 ISX engine) and also with Pete 386's.

A)> First and foremost, that ecm is notorious for this random shutdown issue as they age. You say you have replaced it 3 times but this still does not rule it out. Start the truck up and let it idle ... smack the crap out of the top of the ECM casing. straight downwards, .. almost enough to dent its casing, with the larger end a 1/2 inch extension bar or some other solid object that will reach the top of it ... and see if the engine cuts out. If it does then it is a known issue and therefore a bad ecm.
Here is a nice example of someone replacing ecm and still having this same issue ... : http://rawze.com/forums/showthread.php?t...0#pid12320

AND/OR its is almost always ...

B)> those 386's have a wire that goes to the batteries that is a small one. Maybe a 30 amp fuse or something .. at the battery terminals. That fuse and wire likes to short out causing the ecm to randomly die. here is some info on why they do this...
ref: http://rawze.com/forums/showthread.php?t...05#pid3505

Hamish

I drove a truck acting similar once while passing through Washington DC, wasn't a Pete though. Only happened to find the problem because it was dark out and I saw a hint of blue sparks where a battery cable had worn through and intermittently touching the frame nowhere near either end of the cable. I realized afterward that the intermittent issue was related to torque on the driveline and/or wind on one side and/or if I was parked in a way that torqued the frame, etc.

09Pete386

Thanks Very much guys I’ll be getting to it I a few day, in the mean time I’ll take all the advice I can on this problem or examples of this problem being fixed, weird part is when the first Ecm did that I had it replaced then the second one worked for almost 2 weeks and gave me the same problem but midway into the two weeks I kept getting a stop engine light and throttle position light where my pedal wouldn’t work if it was blinking stop engine unless I was over 30mph and I could use my cruise control to get to where I need to go until I was passing through Warner Robins, GA Saturday early morning this Ecm took a dump on me too at 3am march 25th, that morning I called around a bunch of shops looking for another Ecm found one and the guy was nice enough to bring it over to me, I installed it and it gave me the J1939 datalink, I was told I needed a reflash so I got a rental car and took it to peterbilt in Tallahassee, FL as they where the only ones close enough that where able to do it Monday, after 6 hours of waiting I paid $730 for the reflash drove back ti Warner Robins for 3 hours installed it started up the truck and it gave me that j1939 again, I called the nearest cummins dealer the next day feightliner in Macon, GA and they said if my truck was there they’d fix my j1939, so I stuck my old Ecm in there the second one I purchased started up the truck and went driving there midway truck turned off then turned on, kept doing that until I entered there parking lot and it shut off and just wouldn’t start, it would turn over but wouldn’t start, I’ve noticed that when the engine would warm up it would start doing that if I let it cool that a bit it would start back up until it warmed up, anyhow they got my truck in fixed the j1939 and as soon as I got back on the road out of there lot it did the Same this as the previous Ecm, interning thing is when I had the j1939 no matter how long I’d let the truck run it wouldn’t shut off but as soon as they set all my parameters, it went right back to where I started with the problem, so ye that where I’m sitting at right now, any help and advice would be great, I’ll be going over all the other replies I got and try those things as soon as I get back to it.

JimT

do you have a batter shut off switch in this truck? sometimes when they go bad it can cause a similar issue. Otherwise, check all your fuses, check all your battery cabling like hookliftpete and rawze mentioned.

I personally had 2 different issues with battery cables on my pete that caused this same type of problem. One was a broken lug on one of the two (+) cables that run from my cut off switch at the batteries to the starter, it was arcing on the aluminum battery box when I would hit a bump. That one was pretty easy to spot and fix. The other was a cable that corroded away inside the lug crimp, underneath the insulation. All seemed just fine until I tugged on the cable and it pulled right out of the crimp with a cloud of disintegrated copper dust (that was an off-the-shelf Paccar branded cable).

Also, I've had this error pop up on occasion when the battery voltage has dropped too low when the batteries were excessively drained or when I tried starting the truck while I had a bad battery sucking the life out of the rest.

09Pete386

So I got back to my truck started it up and let it run until it turned off on its own again, then went on doing what Rawze said to smack on top of the Ecm, and it shuts the pump off, I let it sit for a few minutes started up the truck and smacked the Ecm again and truck turned off again, so then assuming it’s the Ecm now, where can I buy an Ecm that wasn’t remaned?

Rawze

(04-13-2022 )09Pete386 Wrote: So I got back to my truck started it up and let it run until it turned off on its own again, then went on doing what Rawze said to smack on top of the Ecm, and it shuts the pump off, I let it sit for a few minutes started up the truck and smacked the Ecm again and truck turned off again, so then assuming it’s the Ecm now, where can I buy an Ecm that wasn’t remaned?

I have not really had any issues from reman ecm's purchased from a dealers#it, but have heard of it happening on the odd occasion. - Just make sure they pre-flash it with your trucks software and settings before leaving there with it. This ensures the ecm is at least working and is cheap insurance against them accusing you of doing something to it / denying a warranty claim if it is a dead stick on arrival. Bang the top of it to test it when u install it to ensure its a good one.