Archived help please batteries wont hold charge/ new alternator

[JRunkal]

1998. 5 dodge ram 2500 turbo diesel 2 new batteries and new alternator all the wires are good batteries will not charge??? the batteries will die while driving cant figure this one out the alternator is good, i tested it?

 

[MMeier]

IIRC, the regulator is built into the computer, see if someone else chimes in here. Oh, and welcome !!

 

[B.G. Smith]

There is a fuse in the PDC where the red wire from the alternator enters, it is a strip of metal (fusible link) and may be blown. bg

 

[JRunkal]

the fuse is fine? the two small red and green wires that bolt onto the alternator are cut off of that black wire thing and run directly to the alternator. chapter 5-7 in the haynes manual shows a picture top middle, the two arrows pointing to the wires is whats cut. dose anybody know how i would get than new wiring part?

 

[icman95]

If the fuse is fine and the alt is really working properly, is there a constant high draw drain on the system that's not supposed to be there? Intake heaters not shutting off for some reason? Other stuff...

 

[JFaughn]

JRankal , electrical issue can be some of the worst things to figure out & can require special tools to do , so I would suggest that you put your location in at the user control panel , some one in your area may be able to help .
You can get an inductive [ touch wire/cable ] amp meters , so that you can look for current being pulled from batteries , dying while driving would seem to be a large draw [ unless its a very long trip ] , that would leave me to think something like the starter or intake heater .
How long to drain charged batteries ?

 

[JRunkal]

about two hours with no headlights

 

[WM-300]

Just had the same problem with my 03 this past Friday. The dealers, service manager told me the grid heater relay was stuck in the closed position. That would sure cause the problem. I pick up the truck in the morning. They wanted it to sit all weekend to be sure.



Paul

 

[WM-300]

Just an update. I picked up my truck today. The service manager showed me one of the grid heater relays that had the contacts burned together.



Paul

 

[GDMRTN]

I had an '03 truck that wouldn't charge. The big charging wire went to one battery and the computer sensed current from the other one. The wire connecting the two batteries wasn't making good connection so the computer didn't see charge. The alternator was charging all it could do into the one battery. So just make sure your connection between batteries is good. Ours was kinda rusty and wasn't making good contact.