Im looking at buying a 91 dakota sport, i believe it has the 5.2 in it, but i am not sure. It has an auto transmission. The issue with the truck is as the owners put it" a charging issue. They said something about getting a trouble code saying something about a short in the alternator field. They said they put a brand new alternator on it and it didnt change. If you jump start it they claim you can drive a little bit with it without headlights and wipers and such on.

What could be the cause of this and where should i look? i wanna get an idea before i go ahead and spend the money on the truck

 

Bad alternator, Bad wires, Bad PCM.

 

say it is the pcm, can you wire up an external voltage regulator? if so what would be a good one to use, and how would i do so?

 

so i actually purchased the dakota yesterday, she will start if battery is charged enough but voltage is at about 9.7V. I checked the two "field" terminals on the back of the alt and both are ready live one at the same as battery voltage and the other just a few less (about .5-.75v). If i ground out the one field wire, the battery voltage will jump to about 16.6v. Im assuming this means the computers internal voltage regulator is bad. so am i able to wire in an external voltage regulator from an older dodge? if so what would be a good one to have?

 

so, i went ahead and wired in an extretnal VR, from a post i found on another site, and all seems good now... I just wanted to double check something tho, my battery while running if tested with the volt meter, is reading 15.1 to 15.3v ( the alternator field ignition source wire is reading 14.8 tho) and it stays steady there... no matter what is on what is running (head lights, off road lights, brake lights) the blower motor doesnt work so thats the only thing i didnt have on when i tested it. do you think this will be fine or is this going to cause other issues...