Hey guys I have a 98.5 Ram 3500 w/24v Cummins i've replaced the batteries and had the alternator checked i work at an Oreilly's so I did it my self and she checks out great. What's not so great tho is the fact that my battery isnt charging. I pust a Volt meter on the cables and show like 11.6 or so volts and if i drivew/ the headlights on for a while at night the batt. dies.yet when i pulled it off the truck it tested just fine. Any ideas on what might be the problem here? Anyone had any problem like this before. Thanks for any help ya'll might be able to offer. Im beating my brains up on this one.

~Phil

 

sounds like a bad wire somewhere in there... if im not mistakin it could even be a bad ground on the battery but if i had to guess from here i would say there is something that isnt allowing the alternator to feed enough power to the battery.....

 

Follow the red battery cable to the power distribution center under the hood. Open the PDC cover. Look for a red 140 amp fuse atached to the end of that red cable. The fuse is bolted to the PDC. If that fuse is blown, replace it. Hope this helps......