The alternator will not charge the battery but AutoZone tested the alternator good then they said it could be the battery well it also tested good. I called a mechanic and he said it could be the wire in the back of the alternator that charges the battery. he told me to run a wire from that post on the back of the alternator to the battery which I did still the battery light is on and it is not charging can someone help me please!!!!

SOURCE: check charging system

Do you have gauges on this car also?
If so, you may have a problem with what is called a "current shunt" resistor. This will prevent the car from recharging the battery....accordianman

SOURCE: not charging

Possibly a fusible link somewhere in the circuit has burned through and disconnected the circuit.A wiring diagram would be needed to look for the location of any fusible links Ohms check the wires involved in the alternator charging circuit to verify continuity.

SOURCE: How to wire up 1975 Ford Courier Alternator w/external regulator?

just put a one wire alt. on it.or test each wire.

SOURCE: car won,t charge the battery the alt is good i had it checked

depending on the year model of your car the voltage regulator is intergrated in the pcm

SOURCE: replaced alternator and battery is good but not charging

I found the problem YEAH. It was the fuse that is in the side of the fuse box under the hood, Its where the battery wire from the alternator connects thru a fuse to go to the battery, Its one hundred and something volt fuse. It took care of the problem instantly.... Thank you all for your replies...