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Full Version: Battery Short randomly losing ECM power w/ign on
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Hello all, I am fairly new to the forum, I’m reaching out for a little help with a new issue I have. First some background to fill you all in.

I found this site after hours and hours of research on how to take care of my emissions system on my 2011 Intl Prostar Premium Daycab Isx 15 Cm871 10 sp man tranny, bought it last year from Ryder in Greenville with 554k miles, trucks in great shape. I tried the egr tuneup but after 40k of local work running 20-50 miles one way carrying liquid fertilizer this truck just couldn’t regen an entire cycle in that amount of time. A few parked regens and a few trips to the local stealership among several thousands of dollars for temporary fixes I found this site and did a full egr tuneup. Again nothing was extremely bad, I didn’t get much carbon out of the system and I wasn’t losing coolant or more than a gallon or two of oil in 10-12k oil change intervals.

After I tried everything I could in my eyes to keep the emissions system running I reached out to Unilevers and demandated my truck. This truck runs 2x better and temps are definitely cooler than before, oil comes out looking much cleaner. Have had it demandated for 17k miles, really the only smoke that comes out is when starting the engine.

My issue with losing Ecm power I believe originated from a battery shorting out on a bolt in my battery box. I know some of you may be wondering how I could let this happen, well I replaced the 4 batteries last winter and there is no strapping system for these batteries in my truck, at least as far as the dealership can tell, Intl relies on the battery box cover to hold them in place. I had to fill in for a friend hauling chips out of the woods since he was having shoulder surgery and my truck went on the chip dumps for two weeks. This allowed the batteries to slide and hence short out on the battery box.

I was left on the side of the road all day (about an hr from home) before I could get a tow truck to come get me. Luckily I was able to get a friend to come pick me up and take me to go grab my retired grandpa’s t800 to get my truck out from under the empty trailer and get it back to the parking lot.

After hours upon hours on the phone with friends (Mechanics) from Cummins and searching, locating, and inspecting wires I am at a loss. Of course as I had almost all day parked safely on the side of the road I was researching this issue. I came across several similar threads but none with the exact issues I’m having. The truck would turn over fine but it just wouldn’t start. Code 1117 according to insite, ecm lost power with ign on. All that code does is acknowledge that the ecm has a communication issue. Sometimes when I key on I temporarily lose the dash and the whole truck does a prestartup cycle with the abs valves and lift pump running when this issues occurs, other times it does nothing and the check engine light comes on and it beeps saying data n/a where the mileage should be and no connection on the dash display.

At this point I have checked and replaced all the related fuses. I found the one on the battery terminal (200a) that runs to the firewall bus (2x 100a) fuses was partially blown. I removed that fuse, and I replaced the two bus fuses. I replaced the inline fuse for direct battery to ecm power (powers the 4 wire plug) even though it wasn’t blown. I replaced the blown 10a fuse inline from the alternator to the batteries. I replaced all the fuses that are not circuit breakers in the fuse box for fear of the dreaded glazing issue. I have replaced the battery that I know had electrolyte come out where it rubbed through on the bolt. I checked all the other batteries independently and they all check out fine. I inspected the engine block ground tap connection for all wires, I inspected the starter ground wires, I cleaned all the battery connections and the frame ground. I replaced the ecm thinking it was bad, the truck wouldn’t start no matter what I did and I got a test ecm through a friend from Cummins and the truck started right up. Keep in mind my truck is demandated so of course there were lots of codes and the turbo was going nuts so I did not drive the truck. Put my ecm back on and guess what, it fired right up and ran, then shut off when I gently hit it against the side of the engine. Now I’m thinking wiring harness issue, so I started wiggling all the wires again and nothing happened. I’ve inspected every ecm power and ground related wire and pin at this point. So I decided to replace the ecm and get it redone by unilevers.

I did that and the truck ran for hours and hours idling and I test drove it 70 miles without a hitch. I got in it headed to the next job, got 25 miles away and it shut off. I waited, checked all my fuses and wires again. Everything looks fine unplugged the ecm, waited a few minutes, plugged it back in and it started up, I made it back to the shop and it tried cutting off on me a few times but i limped it back. It will randomly shut off and not start for hours, it might start right back up, hot or cold, driving or idling. I have had it keep cycling for a few minutes before like you flipped the key on and off every 5 seconds. My issue is that my ecm loses power with the ignition on and the truck dies, randomly. Sometimes it will start right up, I do not lose power to the four wire plug to the ecm.

All of the pins and wires appear to be in good shape from the fuse box to the ecm, fuse box to ign, ign to body controller, and body controller to ecm. Ignition appears to function fine and the truck will turn over in the state of “no connection” , code 1117 on insite. I ensured I found the right wires on the diagrams I had called for two days and had to make a physical appearance to get out of the local dealership who was reluctance to give them up to me.

I have done everything I can think of short of removing the one wiring harness and inspecting each and every inch of wire, or replacing the body controller (of which I have bought a new one) but I can’t program unless there’s a way to do it outside of the dealership for which I would have to get a tow 30 miles one way. I’m going to try to attach a photo of the body controller board that I so very carefully removed, I know how sensitive this technology is and what I’m looking for as far as this board goes. There was some corrosion on the pin from the body controller to the ecm power (pin 39). It also had these green bubbles on it which I’ve never seen nor could I find any information on. This board appears to have multiple layers of circuits so there is some possibility that there could be an issue out of view. I did remove it from the housing and inspect the underside, it looks perfectly fine. This body controller is powered by a wire that come from the area that the bus fuses are in front of the firewall, the same one that the inline fuse for power to the 4 wire ecm plug run off. The body controller does not appear to have burnt up at the power input but I want to hear more thoughts on it. I have contemplated replacing the ignition and started solenoids but since the truck turns over fine I’m not thinking that’s the issue. I would like to replace it either way since I bought a new one and electronics have a limited life so if anyone can offer help on how to go about programing it I would greatly appreciate it.
[attachment=5389]

I apologize for the long post but I wanted to fill everyone in on what I’ve done and where I’m at. I look forward to any and all suggestions. If you’ve made it this far I would like to thank you for taking the time out of your day to read this. I really do appreciate everything that goes on here and I am grateful I found your site Rawze.
sounds to me like you have the dreaded bad ecm (with the well known internal intermittent ribbon cable of hell inside it)... you have replaced the ecm.. it ran for a while,... sounds to me like you got another bad ecm from somewhere... Where was the replacement from? -- if you smack the top of it, and it kills the engine, then simply put, you have most likely yet another bad ecm, simple as that .. I have seen it a hundred times. Only other alternative is that you replace the entire engine wiring harness.

Only other thing I would do is monitor fuel pressure to see if it is not falling off below 250psi while running (or below 75 psi while cranking). If so, could be a snapped shaft on the gear pump that is catching sometimes, and at other times, slipping.
Unplug the 4 pin power/ground plug from the left side of your ecm, take your low beam bulb out of your headlight, use a couple Male and female butt connectors and 2 pieces of wire to make a harness to run your headlight bulb off that plug...... there is a constant power wire, a ignition wire (this is the one losing connection) and a ground on that plug. That bulb should light up bright, if its dim then the wiring is bad.

Another thing is your ground and power wires run up to your drivers side firewall where your mega fuses are, on the inside of your firewall is the opposite sides to those posts and they can get corroded real bad as well as remove your foot panel by your BCM and look up there.

The ground that goes from the starter to the frame also has the wire attached to the same frame bolt that runs up to your firewall so all must be clean. If you have a ohm meter do a resistance test on all grounds to ensure they are good.

https://www.thetruckersreport.com/trucki...ay.272033/

Hope it's ok to post other forums links because I hijacked this thread over here and documented what I did to find this issue on page 8 I think..... it shows the headlight bulb test too.
Rawze, thank you for the quick reply. I have done the tap test with a screw driver and mildly with a small hammer to no avail on this “new” reman ecm. I got the ecm straight from Cummins (still haven’t turned in my old one for a core).

Brock, thank you as well, I will have to try your headlight test tomorrow. All of the ground connections are in good shape, including the ones right on the firewall, no resistance in any of the ground wires or in any of the power wires directly related to the ign/ecm. Where did you measure the resistance for the terminating resistors?

I’ve been trying really hard to figure out what could’ve been damaged from the battery shorting out on the battery box/frame.
My terminating resistor on my 08 prostar was on the drivers side inside frame rail right beside the transmission.
I meant to add that this issue with losing ecm power will happen without the truck running. What I mean is if I leave the key in the run position it can and has randomly cycled the abs valves and lift pump and then will lose connection randomly. I’ve had it cycle several times before without me doing anything or shaking the truck even.
Mine did the exact same thing.... but mine ended up being the ecm. I literally cleaned every ground and pulled the harness apart engine to fuse panel before figuring it out.
[attachment=5394] Go back to the battery box and recheck the fuse holders. Break a fuse in half so you can drag test the female connections one at a time. Better yet take pliers and gently squeeze the the terminals to tighten them up. Often the truck side of the fuse holder will loosen from heat and lose contact. Both side of the fuse will test good but the blade of the fuse isn't making contact. Have also seen the wire connection where it is crimped into the battery terminal get loose. Also if you have "cube" fuses make sure they are OK and the connections are tight. They are about 1 inch square and will be right on the battery post. There will also be some 2 and 3 wire connectors. I will post some pics. Take them apart and look. If they are bad it will show. I usually cut them out and hardware. They cause a lot of intermittent problems. Take the nuts off the mega fuse or fuses and make sure all the terminals are secure on the wires hooking in. The starter hot post is used as a junction. The terminals on the wires there can be broken, they look OK but aren't. The load test with the head light is a good test. Thought I had better pics in file.
Brock, I did the headlight test on the 4 pin connector for the ecm, passed with flying colors. I didn’t get a chance to check the terminating resistors that’s on the agenda for tomorrow. I saw where your ecm was disconnected in that thread. What are the odds this reconditioned ecm is also a fluke? Could my old ecm even have been damaged by the short since the 15a inline fuse from the batteries wasn’t blown? Also I want to make sure that it’s correct without the ignition on that I can power the bulb from both hot lines on the 4 pin.

DVT873, I will also try to follow your suggestions tomorrow. I removed the block fuse as it was partially blown and I thought that was the source of my intermittence. I will check the starter wires and bus fuse connections again. I was very tempted to remove the inline fuses as I saw a few people with similar issues and that seemed to be the cause.

Huge thanks to you all I appreciate your time and suggestions!!
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