I've got a 99 3500 that I've had some charging issues with....mainly the plug on the back of the alternator not connecting well. I decided to remove the burnt up plug and replace it with some female spade type connectors. It had quit charging all together before removing the plug, I assumed the plug was bad. Now after replacing the terminals it still does not charge. I got a new alternator, installed it, still no luck. Can anyone point me in the direction as to how I should diagnose this? What can I check? Should I get any voltage from the 2 small wires on the back? I'm clueless at this point. Is there a fuseable link anywhere that could have blown? Any help would be greatly appreciated!

 

the computer controls charging so you might need a new one

 

Check your fusable link on the drivers side wheel well under the hood inside the fusebox. IF that is popped you wont charge. take a peek at that before you do anything else.

 

Are you talking about the one labeled alternator fuse? Already checked that, its good.

 

Its located in the fuse box atop of the drivers side wheel well. Its right on the side where the red and black battery wires come into the box.

 

Yep, checked that, its good.

 

well then im stumped....

 

I've narrowed it down to the green wire at the back of the alternator. Everything else is right. Still trying to figure out exactly what it does, I do know by the wiring diagrams, that it goes to the PCM.

 

The green wire is your regulator wire...regulated to ground through the pcm. The blue wire should be key on power.

 

mine did the same thing. the ecm on the fire wall fixed it. i got a new one. its not too expensive from a salvage yard. just try to get a match on what your truck is.