I need help, about a week ago my alternator went out on my 2000 ford ranger 3.0 4x4 so I got a rebuilt alternator from a good source where I've always gotten alternators from in the past but now with rebuilt alternator an a new battery I'm still getting low voltage and battery light. I put my voltmeter to the terminals an I'm only getting 12.5 volts with the truck running should be around 14.6 with truck running I've checked all fuses in the engine bay an dash all good fuses even replaced the alternator fuse just incase and now my radio isn't working aswell any ideas would be appreciated

Have not checked the "fuseable link" can not find location or just the word on the grape vine thanks in advance

 

Welcome to the forum

You don't have fusible links in 2000 Ranger
Key OFF
Use volt meter to test B+ terminal on the back of alternator, its the stud nut terminal, ground meter to alternators metal case for all tests
You should see 12v, battery voltage, that means 175amp Mega Fuse is OK, if you don't see voltage then that fuse is blown

Unplug the 3 wire connector on the back of alternator
test Yellow wire, should see 12v, if not 30amp fuse in engine bay fuse box is blown

Test light green wire, should be 0 volts
Turn key on(engine off)
Re-test light green wire, should see 12v now, if not then fuse 15 in cab fuse box is blown, this is also the Battery Light fuse, so if you don't see battery light when you turn key on(3 wire connector hooked up) then fuse is blown

If all 3 wires test OK, and the white jumper wire is plugged in to spade terminal then truck side of the charging system is OK

Start engine, test battery voltage, should see 14-15volts, if not then new alternator is bad, period, charging systems are VERY easy to test, 3 wires easy