Ok so Monday my passenger side battery started boiling it had a 03 alternator on it so I changed out the alternator and both battery's Tuesday. It's still boiling the passenger battery and the new alternator is putting out over 19 volts when on truck but when it's taken off and tested its running normal and the battery gage inside the truck drops to 8 when passenger battery is hooked up but when I take the passenger cables off everything goes back to normal. Can anyone help on this. It's a 2007 dodge cummins 3500 4x4.

 

If I recall correctly, the voltage regulator is part of the PCM, which means either you have to get creative and buy an old-school external voltage regulator and hack it in, or replace your pcm.

At least that's how it works on older Rams. You may want to do a little more research before attempting: http://www.thedieselgarage.com/forum...ad.php?t=58251

 

Thanks horatio102 I will look at that tomorrow and see if it helps my truck.