Yellow/white Wire On 3g Alternator - Placment ?

Igofaster13

Member
Mar 9, 2006
168
3
19
San Diego
I have been looking at all the diagrams/threads on the wiring of the 3G alternator, and see different setups for the yellow/white wire. One way is to leave it be on the connector, and the other is to connect to the B+ post of the alternator, running through the 4awg wire and fuse. If connected to the post, cant I eliminate the old wiring for the 10awg black orange, as the yellow/white connects to it down line?
 
  • Sponsors (?)


You can but it would not recommend it. If for some reason you ever had to swap back to the original alternator, it would not be correctly connected and the alternator would not work. Leave it and the black/orange wires intact and don't cut any of the ends off the wiring.

Alternator wiring.

attachment.php


Starter solenoid wiring 86-91 model cars.

Connect the fused 4 gauge wire to the alternator and the battery side of the starter solenoid.
attachment.php


Starter solenoid wiring 92-93 Model cars.
attachment.php
 
Thanks.. But seen that diagram with the others. I think the Y/W to B+ post on alt is more direct for voltage sensing purposing. There has to be voltage drop levels in the old wires (org/blk>wht/yl) messing with the regulator. Personally this will never go back to stock, & if it ever does its a short trip down to the PYP yards for another harness. SO... anything wrong with eliminating the wires and running the w/y wire straight to B+ alt post?
 
Thanks.. But seen that diagram with the others. I think the Y/W to B+ post on alt is more direct for voltage sensing purposing. There has to be voltage drop levels in the old wires (org/blk>wht/yl) messing with the regulator. Personally this will never go back to stock, & if it ever does its a short trip down to the PYP yards for another harness. SO... anything wrong with eliminating the wires and running the w/y wire straight to B+ alt post?
The yellow/white wire is the voltage sense wire. It's purpose is to sense the voltage drop between the alternator output and the battery positive junction point. If the output is low, the regulator compensates by raising the voltage at the alternator output terminal. A difference of a few tenths of a volt can mean the difference between a fully charged battery and a perfectly working electrical system and one that has a low battery and problems. For that reason, the yellow/white wire needs to remain intact and not short routed back the the alternator output terminal.

attachment.php
 
I agree with the wise words of JRichker. We're more about function over aesthetics however.

If the stock wiring really bothers you, you could subtly run your own sense wire (with appropriate circuit protection) back to the solenoid or battery.