3G Upgrade Question

[Robt.Webster]

Finally installed my new 3G high-output alternator on my 92 F350 today. It works as advertised putting out lots of current at idle like never before. Only one small issue, the alternator warning light on the dash to the left of the steering wheel stays on all of the time now.

I realize that I can just remove the bulb, but I would rather have the warning light working properly as it would warn of a thrown alternator built while traveling down the road.

I don't have access to my wiring diagrams, so I was wondering if anyone knew what drives this lamp? Has anyone encountered this problem and fixed it?

Appreciate any help that anyone can provide.

 

[cpdenton]

From what I can tell, there is a light green/red wire that needs to be hooked into the internal regulator of the alternator.

It should be on the 3 wire harness on you 3G and the same color wire should come from the truck harness that went to your old regulator.

 

[Robt.Webster]

It appears as though you are right looking at the connections on the old alternator versus the new. Unfortunately, the alternator supplier cut this wire off flush with the plug. May have to source a new plug so that I can make this connection.

 

[LCAM-01XA]

Who is the alternator supplier, and what is the factory application for said alternator? The only time I've seen the trigger wire cut off like that is on self-exciting alternators where you have to revv-up the engine a bit to get them to start charging (after which you can let them idle down no problem). The fact that yours seems to be charging without the trigger wire sure makes it look like a self-exciting unit... Not sure what will happen if you hook the trigger wire to those.

 

[OLDBULL8]

Is this your 3G connection.

 

[Robt.Webster]

Thanks, OLDBULL, it will be as soon as I get a new plug. Can't figure out why they cut the wire that I need flush with connector

 

[franklin2]

Thanks, OLDBULL, it will be as soon as I get a new plug. Can't figure out why they cut the wire that I need flush with connector

If you read one of the previous posts, they probably cut this wire because they put a special regulator in your unit. The factory 3g would not charge without this wire hooked up, so I would say it's very likely they did install some sort of special regulator, and the chances are high that even if you hook that wire up, it's not going to work the light properly. All you needed was a factory 3g from the store, not a special unit like you bought.

 

[typ4]

The self exciting reg should still operate the light.