Hi all, this is my first time posting anything here, I have been using the forums as a resource for my truck since I bought it a couple of years ago and it has been a big help, thanks.
I have been having some trouble with my truck and I'm not sure whether the problems are linked or not. First of all, a couple of months ago, after an oil change, I started to have trouble with the engine turning over slowly and then after a while, it wouldn't turn over unless I boosted it, after it sat for a couple of days. I cleaned the battery terminals and it helped but it still turns over slowly, I just haven't had to boost it since.
Then, the other day my wife took it to work (oops , it's about half an hour on the highway, and about half way there the "Check Gauges" light comes on and the voltage is way up at 18V. She drove it the rest of the way like that and when she got to work she shut it off and started it back up and it was charging normal again. I drove it home that day and it was normal (14V on gauge approx) all the way home, haven't started it since.
Are these problems linked? From what I've read it sounds like maybe the PCM?
It's an '02 2500 Cummins 6 speed with 230,000km, 140,000 miles

 

Have you checked the batteries? I have an 06 that had the same problem, checked the batteries, and one would not hold a charge. I changed both, and it turns over fine now.

 

load test ur batteries... disconnect both and load test them U have 1 bad battery....

 

Thanks, I'll give that a try. Will that cause the overcharging issue as well?

 

It can

 

Never did add the results to this thread. Replaced both batteries and the problems went away, just as the guys mentioned above. Thanks all!