Yellow wire from alt.? where does it go to?

[woodbutcher5691]

Had someone tell me there shouldn't be any voltage at any connections to the alt.
With the key off. I'm getting 12v on the yellow wire all the time so that probably what fried the alt. It goes over into the fire wall on the drivers side. Anyone know what circuit it feeds into? Thanks. This thing is going to run again one way or another. Carbed 302 ?

 

[RonD]

Alternator couldn't charge battery if it wasn't connected to the battery

I assume Generation 2 alternator, so internal voltage regulator

On the back of the alternator is the B+ terminal, it has the larger wire hooked up, that connects directly to battery thru a mega fuse or fusible link, it should always show/have 12volts(battery voltage), key on/off doesn't matter

The 3 wire connector on alternator will have a Yellow, White and Light Green wire
Yellow wire can be connected to B+ or have it its own fuse and be connected to the Battery, so it should always show/have 12volts, key on/off doesn't matter

White wire is a jumper from voltage regulator to Fields in alternators case, so just a short wire.

Light Green wire is the ON/OFF switch for alternator, it is also the Battery Light wire.
It will/should have 12volts only when key is ON, engine off.
If Battery Light isn't working, then could just be a blown fuse in cab fuse box, Battery Light NEEDS to come on when key is turned on or alternator can not start working.