GMC Truck Forum banner
1 - 11 of 11 Posts

·
Registered
Joined
·
251 Posts
Discussion Starter · #1 ·
Last month my voltage was dipping on the volts gauge and the battery light would flash on and off. I tested with a multi-meter and the battery read 12v off and 14+v on. Sometimes though while running NO voltage was outputting from the alternator.

Autozone bench tested the alternator and said it was good. I went home put it back in and it was cool 14v all the way, no light. I drove it about 100 miles no problems.

Drove around today and voltage dipped below 14v and battery light came on. I ignored it and now my truck is in a parking lot until tomorrow.

Does this sound like a bad alternator even though Autozone says otherwise. Give me some feedback!!!!
 

·
Registered
Joined
·
3,843 Posts
or maybe the fuseable link from the alt to the little red batt box. Buddys truck kept saying not charging battery replaced alt, still same problem. turned out the fusible link had melted the plastic between the ring terminal and contact in that little red box causing no connection. Would never have seen it without taking it off. looked normal all around. just melted right up under it.
 

·
Registered
Joined
·
251 Posts
Discussion Starter · #4 ·
I have checked continuity between both ends of the fusible link and Im getting a beep from my meter. I have not checked for melted plastic up under the terminal, but if i check continuity between the alternator pole and the positive terminal I get a beep showing me that nothing is preventing the path of voltage. When I put my lead on the bolt coming straight off the alternator I am not getting 14+v. The alternator appeared to not "constantly" be outputting voltage.

the truck is an 02 and this is the original alternator. Also when the truck is running if I disconnect either the negative or positive on the battery the truck shuts off. This has been know to be an indication of a bad alternator

There isnt anything that would keep the alternator from "turning on" or charging would it?

Like when the truck is running the alternator should be putting out voltage. Right?
 
1 - 11 of 11 Posts
Top