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Dying ECM?


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I just got home and unhooked the signal wires to the alternator. Started the truck up and the grids were cycling but voltage was only around 11.8-12.0 because batteries need charged. Truck still shut off after a few minutes. Any chance the ecm needs charging voltage to run right? I'm ordering an ecm tomorrow unless there is a chance that it's doing it because of the low voltage now. Either way I'm going to paranoid the rest of the time I own this truck at this point. Might be time to get rid of the old girl after I hopefully get it fixed. 

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Forgot to send the below when I typed it. But yes if the voltage is low it can cause weird problems. I am thinking that is part of the problems i am having right now. Seems my batteries are a little weak and they are not quite 2 years old at the moment.

 

When you call Cummins just give them the part on your existing ECM. They don't know nothing if you tell them it is on a Dodge. They work with part numbers and engine serial numbers. I hope they still sell them, the one on my truck has lasted almost as long as the new one that came on it. It was a reman even back then.

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ECM required voltage above 8.0 DC volts to keep running. The dash gauge is not accurate at all. After it drop below 12.00 volts on my truck it instantly drops to 8 on the gauges, rings off the check gage light and there it sits. 

 

Make sure to drive it around awhile and then pull the alternator field lead that way you don't have the grid heater fouling you. Or... Warm it up then disconnect the grid heater lead at the battery and the alternator too. Then you'll get a better test run.

Edited by Mopar1973Man
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I was getting the voltage reading from the pulse monitor which measures ecm voltage. Even when the grids ran it was just for a split second and didn't pull it down below 11 volts. It was showing 59 on the overhead temp. Unfortunately it's undriveable in its current state. When I tried that test last night and it quit running I sat there for about a minute and cycled the key on and off a couple of times waiting longer in between each cycle and the ecm still hadn't rebooted to give me the lift pump circuit or the wts light. It's getting slower and slower each team. I was hoping that the ac voltage hadn't already killed it and I'd be good to go after fixing the alternator but I'm afraid it's to late. I've had the batteries on trickle charge since last night. Well one last night and then I switched to the other one before leaving for work this morning. Going to give it one more chance when I get home today but I think I'm just delaying the inevitable at this point. I could swear I checked ac current when I bought this alternator but maybe not. Really disappointed in what I was thinking would be something that I wouldn't have to worry about. I found the box for the alternator last night, and my old one inside it too, and of course I bought it 2 years and 5 months ago and their warranty is 2 years. I'm waiting to hear back from mechman to see what they say about being able to guarantee me this thing is rebult and comes back with absolutely no more than 40 mVAC. 

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Thank you for the help on that.  So if I understand you correctly when they bench this thing at full load 1 volt or slightly more is or should be acceptable when I get it home and bolt it back on the truck and do our method of measuring it at an idle? I'm just worried I'm going to waste my time and money sending it down there for them to try and tell me there's nothing wrong with it. It's 5 months out of warranty so I'm hoping they make it right and take my money and move on.  

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Tonight's update... after trying get something through Cummins on Friday and Saturday to no avail I called up the place I mentioned before. Their website is dieselecmusa.com but their storefront shop is diesel system services in El Cajon California. The guy that I spoke to for about half an hour seemed like a respectful guy but you can only tell so much through a phone. He wasn't in a hurry to take my money and is actually calling me back in the morning after he speaks with the place who builds them. He will give me the lead time and then take my money unless someone shares a horrific story on here about them.  He said the company he gets them from is the same place that the dealership and cummins had their contracts through. I forget most of what he said during that time so those may not have been his exact words so I don't want to put stuff in his mouth. But basically whoever this company is that he gets them from only deals with contracts and even he cannot get most other computers because they are in contract with someone else. The computers for our trucks are no longer under contract. Just makes you wonder who the company is... I'm going to put my faith in the fact that not everyone can be a liar and give him quite a bit more money than what other places are charging based on if what he says is true about the product I will gettung back then it is worth it.  I pray it turns out good because we really don't have any other trustworthy options it seems. 

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Well the saga continues....I just couldn't sleep laying here thinking about it was some sort of a sign that he didn't get my card info to pay for that ecm tonight. One thing I believe that I didn't try up until this point was to unplug the quadzilla. It's a long shot but I couldn't sleep until I tried cause I won't have time before I leave for work in the morning. So I go down to the truck at almost midnight and pull off the belt because the alternator is on it's way to Tennessee and then plug the ecm back in and hook up the batteries. I simply unplugged the adrenaline at its harness connection and fired up the truck. I'll be darned if it didn't sit there an idle not skipping a beat for 20 minutes. So I plugged in the scanner and cleared the codes and the restarted. Only code that came back was the map sensor 0237 because I didn't unplug the adrenaline harness. So now it's one more day of waiting and wondering. Everyone said how rare it is for the ecm to crap out and being it was only giving me one or two codes I just couldn't rest without exhausting all my options.  I am praying that this is the actual problem. I've had problems with this thing freezing and just not working but I kept thinking it was a voltage problem because of the truck not charging above 13.2 when it was hot outside. It always seemed to freeze at 12.9.  So it's getting the alternator rebuilt, new batteries, and praying it's just this crazy adrenaline and it didn't kill anything else.  It would be such a blessing if that is the problem and the ecm isn't fried. JKidd bought quadzilla, right? Looks like I'll be giving him a call tomorrow to pick his brain and get this thing fixed or replaced cause I can't go back to a stock truck after driving it this way for 7-8 years. Keep your fingers crossed for me

 

 

 

 

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I hope it turns out to be the Q also. I cringe every time someone even mentions a fried ECM since a reliable one seems hard to find and a sure diagnosis is not always easy. I was pretty much on my own when mine went. Nobody seemed to know much about them when mine went 8 years ago. And a new one would not have solved your problem. Thats another reason we are all a little gun shy of condemning one. 

Edited by dripley
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The thing is this whole time I kept thinking that pulling the quad off was one of the first things I did. But the more I think about it I don't believe I actuwlly did. I planned on it and then without thinking I was excited to try it after putting on the new ground cables that I plugged everything back in and started it up. I brought the quad with me to work so I'm going to open it up if it isn't to hard and have a look 

This is a 4K adrenaline. Yeah I know.... I thought I had different plans for the truck and I had a regular adrenaline fry itself on me under warranty. So they were kind enough to send me back a 4K module instead of a regular one. Tuned around it's issues the best I could and didn't have any problems daily driving it because I pretty much drive like a grandpa. I'll be darned if I see anything obviously wrong with it though. Then again I don't exactly know what I'm looking for either besides burned components. 

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Something would definitely have to be fried for me to see anything wrong in all that. I am dealing with a 237 code at the moment. Keeps dropping in and out of limp mode. I guess I had ought to disconnect my Comp and see if it is part of the problem. Way to many connectors at the map sensor. Just might be the cause.

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You may want to just pull out the map sensor and inspect it. I'm sure it's probably dirty if it's never been cleaned and the comp box has been on for awhile. Or at worst replace it which used to be between 80-100 bucks I believe but that was a few years ago. A co worker of mine did find a spot on the board where there appears to be a missing diode but I can't tell if there was ever meant to be one there or not. In the second picture at the top middle/left there is a string of 7 or 8 small diodes. Third one from the left is missing. Unfortunately I haven't been home yet so I can't confirm the problem has been fixed just yet. I am nervous and excited at the same time. Still cannot believe I went through all of this without pulling the box first. I knew better and for some reason I was thinking I did at the time. What an adventure this has been. 

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See I've been away from the forums to long. A lot has been learned since I was last active. Well my I'm sure my neighbors hate me at this point. Got home and started it up on fresh charged batteries and went inside. 12 minutes later I heard it hiccup just like it did when the cam sensor started dying and shortly later went out a couple years ago. Then two minutes after that it died. I was down at the truck again at that point. I cycled the key off and back on and the wts light immediately came on. Ok. So check the codes, 1689. Start it up and a couple minutes later it died again. Cycled the key and nothing. Did it two more times and nothing. Let it sit the third time with key on for about 20 seconds still nothing. Read the codes, 1689 again. Cycled the key and it started just like it should and then died again about a minute later. It's driving me mad. I'd rather replace the pump or throw a new cam sensor at it but the delayed wts is what is telling all though I believe. But to be clear I've never cycled the key on and sat there long enough for the wts light to kick on. Idk if it ever would. I just cycle the key back off and on again and it either works or it doesn't. Man I really don't want to buy an ecm for this thing.....

Edited by Curt026
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11 hours ago, Curt026 said:

You may want to just pull out the map sensor and inspect it. I'm sure it's probably dirty if it's never been cleaned and the comp box has been on for awhile. Or at worst replace it which used to be between 80-100 bucks I believe but that was a few years ago. A co worker of mine did find a spot on the board where there appears to be a missing diode but I can't tell if there was ever meant to be one there or not. In the second picture at the top middle/left there is a string of 7 or 8 small diodes. Third one from the left is missing. Unfortunately I haven't been home yet so I can't confirm the problem has been fixed just yet. I am nervous and excited at the same time. Still cannot believe I went through all of this without pulling the box first. I knew better and for some reason I was thinking I did at the time. What an adventure this has been. 

I just installed a new sensor not long ago. The old one had been in the truck for years. I had also swapped in the oe sensor about 3 months ago but it broke and I had to reinstall it. Never cleaned it. Messing with the wiring harness and all the connectors did however cure my surging issues and apps codes I was getting. I then started getting the 237 code and limp mode. Just swapped one problem for another. That is all making me believe mine is wiring issues and possibly to many connectors at the MAP sensor. Sensor cleaning never did anything for me.

 

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Parts guy from cummins called me back today and informed me that his computer wasn't up to date when he was looking for stock yesterday. (I called another cummins place). Apparently there is an ecm for my truck. 2500 bucks and would need programmed. Ouch. He talked with a tech there that owns a vp truck and I was instructed to call back in the morning to talk with the service guy about scheduling an appointment and they can test my ecm. I'm worried though that since the problem only appears for the first time about 10-15 minutes after the truck is started that it may test good?  Is there anyway possible that the pump is going bad and when it stalls the truck some kind of memory or something is still telling the ecm that it's on so therefore the ecm isn't rebooting right away? I am seriously worrying myself almost to the point of insanity over buying an ecm and it being something else. Does the delayed wts light always point to bad ecm no matter the cause of what it took to get it to do that?  It is only ever delayed after it shuts off from 1689 code. What a mess

 

If I Hotwire the pump and it still dies then that means it's the pump and if it doesn't then that would be ecm, right? 

Edited by Curt026
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32 minutes ago, Curt026 said:

Does the delayed wts light always point to bad ecm no matter the cause of what it took to get it to do that?  It is only ever delayed after it shuts off from 1689 code. What a mess

 

If I Hotwire the pump and it still dies then that means it's the pump and if it doesn't then that would be ecm, right? 

From what I know 

Delayed wts points to ecm not booting.

If you hot wire the vp and it runs means vp it good. 

:shrug: wish I knew more, don't want to miss lead.  

Sometimes you can find used ecm on Craigslist or something like it for few hundred bucks. Be nice if you knew someone that could let you borrow ecm from same truck to rool it out.

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You're telling me...man what I wouldn't give to be able to do that. Decided to run through all the 1689 tests again. Everything checked out as I moved down the list, very little resistance, until I got to the last one. Checking ohms from pin 1 on the vp connector to battery ground I cannot get anything. Just shows open loop.  I don't remember having this before when I tested last week.  From battery ground to pin 6 I have continuity but nothing from 1 to ground. What am I missing? That's with batteries connected and disconnected.  Im pretty certain that's the test I tried right before I disconnected ecm just prior to running through all these tests again and I had a reading of greater than 5 ohms.  *plugging the ecm back in to check

 

 

yeah continuity from ground to pin 6 with batteries hooked up. Nothing with batteries unhooked. Still open loop from vp 1 to ground with ecm unplugged/plugged in and batteries hooked up/unhooked. Does this mean there is a wire broken? Or am I screwing this up

 

 

 

Man this is weird. I get open loop with black lead on battery ground and red on pin 1. But I can touch pin 1 to other stuff and get a ring. Switch leads around so black is on pin 1 and red to ground and instantly get a ring and -70 ohms. Wtf? Black on ground and red on pin 6 and it rings instantly.  I've moved wires all around trying to find a short or something but it's dead silent. I'll stop posting so much. I'm tired of myself at this point. Hopefully she's back on the road soon

Edited by Curt026
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50 minutes ago, Curt026 said:

yeah continuity from ground to pin 6 with batteries hooked up. Nothing with batteries unhooked

Pin 6 is the power (battery) ground for the vp44 so this reading is correct.

 

54 minutes ago, Curt026 said:

Still open loop from vp 1 to ground with ecm unplugged/plugged in and batteries hooked up/unhooked. Does this mean there is a wire

This is a data ground.  It grounds in the ECM.  This type of ground will either show very high resistance or open circuit at the battery.   Black wire should show continuity between injection pump pin #1 and ECM pin #23. 

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Very good info. Thank you for the reply. Well everything checks out then. Just very tripped out by the open loop or 75 ohms reading when I switched the multimeter leads around from pin 1 to ground. I just keep trying to find any excuse possible to not have to go through the heartache of getting an ecm. I've shied away from diesel system services because of the no returns and and one year warranty. That and I just can't help but believe I'd be paying more for the exact same thing I'd get elsewhere. If they did it in house then yeah sure. Goecm seems to have the most positive reviews I've seen so far. Lifetime warranty on their units or I can even send mine in for repair for what I'd expect to be considerably less than the 800 they charge for a refurbed unit. 

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