URGENT!! Charging problem!

[raceman]

Im not allowed to post in the 911 forum for some reason. I have a 1991 Ford Ranger 4.0 and i recently (3 weeks ago) bought a new altenator an put it in and ran fine. Battery is maybe 3 months old. Last night while driving at night all my lights got dim and my battery check light was on an volt gauge was reading way low. It still ran fine so I drove it 10 miles max and got it home and it just died when I got it in the driveway. Today ive been tinkering with it( charged the battery, checked wiring over and over and over) nothing. Battery has a solid 12.5 volts and alternator is also putting out about the same using a multimeter. Checked the 15 amp Alternator fuse in the fuse box and its blown. Tried putting another one an and the same thing! It just keeps blowing them. Took the positive cable off and ovbiously it allowed me to put one in but as soon as I hooked the battery cable back up it instantly blew! Im extremely frustrated and need urgent help!

 

[FirstOnRaceDayy]

Fuses blowing is a good sign that a wire is shorted to ground

 

[Elessar65]

fuses blowing is a good sign that a wire is shorted to ground

x2

 

[wood1]

An alternator usually puts out 14 or so volts. Maybe you are just running on the battery and it's not charging. With the blowing fuse I would suspect the alternator and or wiring for it.

 

[raceman]

Ya took the alternator to advanced auto and they tested it and it was only putting out 8.3 volts to the battery. I got a wiring schematic printed off at work (work at a car dealership) of the charging system so im hopeing to find the problem. It shows that the fuse also runs to the ABS so im hopeing I dont have to go through all of that

 

[wood1]

I was thinking that an internal short in the alternator was causing the problems with the fuse. Was that not the case?