I have a 91 dakota, the battery went dead and i had to jump it off. i had the battery tested and it tested good so i figured it was the alternator not charging. My uncle works at NAPA and gets parts at a very good discount, so i had him order me an alternator. i replaced the alternator yet it's still not charging, i had it tested, tested good. so at this point im clueless, alternator and battery are both good. what else could it be??

thanks
Craig

 

They might seem clean but did you run a brush through the cables.Could be a thin film of black death.

 

I have a 93 dakota 5.2. The charge rate is controlled by the ecu mounted on the fenderwell. Have you used a volt meter and checked the charging voltage at the battery with it running? Should be around 14 volts. Also possible you melted a fusable link in the wire harness. Before you start replaceing parts, get the wiring diagrams from a hays manual and check for fuses. Also check the system fuses mounted on the drivers side fenderwell

 

Update Found out a couple weeks ago that my brother was having problems getting it to crank and he let his buddy pull the battery cables. His buddy touched the positive with a wrench to the body [:@] my brother said smoke was rising from under the hood and that the wrench started glowing... BLAH So i went through the entire harness and checked every fusable link in the harness with a voltmeter. Everything checked okay. so now im beginning to think maybe the ecu is fried . What do you guys think? how can i tell if the ecu is fried. I just purchased it 3 months ago from autozone so i will see if i have some type or warranty

Thanks!!

Craig

 

Dodge ECUs are very reliable. I picked up a couple spares for those long road trips,but have never had to use one. I have seen several poeple kill them from just doing stupid things like sparking the booster cables. Those ones would not even restart.

 

Well I visited the local junkyard today, they had a computer for 30 bucks. I bought it and put it in.. Voila, fixed everything! the trucks back to being my reliable mode of transportation again. Thanks for all the help!

 

Disconnect the battery first. Most newer alternators have the voltage regulator built into the alternator itself. Especially if is a factory nippondenso part.