I have a 99 dodge ram 2500 with 24v cummins. A year or so ago I had an issue with my ECM. The throttle was stuck at 14%. I bought a new one through GO ECM DIESEL and it had a lifetime warranty. About 8 months after having the ECM my wait to start light wouldn't come on anymore. I put my buddy's ecm on my truck and the light and grid heaters worked fine. Mind you I've always had to wait for the wait to start light to go out before the truck would start, ever since I've owned it. I've owned it for about 2 years now. When I first got the ecm it would start fine with the WTS light on. After a while it was back to waiting until it shut off to start the truck. Then my grid heater and wait to start light quit Completely, that's when I threw my buddy's ecm on my truck and it worked fine. So I warrantied my ecm and got a new one. The ECM worked great for probably 2 months. It allowed me to start the truck with the wts still on. After 2 months it was back to waiting till the light went out to start it, now about 5 months later, once again I have no wts or grid heaters. Any idea?

I looked at the web site where you bought your new ecm and there are many available, did you get the correct unit ?

Yes for sure the correct unit.

Sounds like you have a bug in the system that is killing your ECM's. Maybe the alternator is causing to much AC voltage?

I wondered that. When I first had troubles I called mopar man and he told me it was the ECM and that the ECM doesn't just fail, something must be causing it. But sometimes everything will work like normal after a few months of no wts.

An average run of the mill voltage meter cannot read the correct amount of AC noise the alternator is throwing out. I had to go get a good Fluke volt meter cause my other one showed 30 volts ac on every vehicle I tried it on. The new to me Fluke showed my Alternator was marginal at best so it got changed out before any damage.

Also like Mopar Mike says, it is good to disconnect all grounds and charge each battery as the chargers are bad enough on AC noise to hurt the ECM while charging also.

My 98 starts this time of year w/o WTS. But w my 2000, it can be fully warmed up if I shut it off, I have to treat it like it's a cold start. Other than that it's ok!

Does it start even thought the WTS light isn't working? Reason I ask is years back when I first got a smarty programmer for my 02 I did my second download the day I got it and I was in the middle of no where about 40 miles from the closest town delivering a trailer to a guy at a meeting point and in the middle of the download it aborted and I lost the WTS lite and had a no start, found out it was a dead driver in the ecm that sometimes go bad during down loads, Smarty via Bob Wagner overnighted me a new ecm and I was on my way after a pull back home from the guy who was picking up the trailer lol.