Alternator Wiring

[lenleg]

I have my MK4 at the test driving stage with the body on for the summer. We have stayed close to the shop as we worked out brake problems. Got them corrected and drove 10 miles from shop and noticed the alternator9New) was not charging. I have the 302 V8 engine and put a new alternator for the 1990 Mustang. It is the type with 2 plugs ... 3 wires from each plug. I have the Ron Francis wiring kit.


A Top Plug (3 wires)
Blk Orange
Brwn Orange
White

B Small Plug (3 wires)
Green Red
Yellow
Yellow Blk

Here is how it is currently wired ... can someone please tell me the correct way to wire it?

A White - B Yellow Blk
A Blk Orange & Brwn Orange - Red Alternator FD (comes off starter solenoid)
B Yellow - Brwn Alternator Ign (from fuse block)
B Green Red - nothing

[Mastertech5]

The alt is wired using the engine harness for the engine you are using. It doesn't have anything to do with the Ron Francis kit other than your voltage gauge. You need a Ford wiring diagram.

[FF33rod]

The alt is wired using the engine harness for the engine you are using. It doesn't have anything to do with the Ron Francis kit other than your voltage gauge. You need a Ford wiring diagram.

Only if it's an engine with an ECU, like the Coyote. Old 302 SBF engine wires direct into the Ron Francis harness.

I have a 1 wire alternator that came with my front drive system. Will take a look at the documentation I have and will edit this post if I find something relevant that helps....

Steve

Addition: This may help https://www.youtube.com/watch?v=8LGP4mmtx-8 According to the Ron Francis wiring instructions (common manual for roadster, coupe and hot rod) the harness should plug right in to a 1990 alternator.

[rich grsc]

188200

[Jhinkemeyer]

The "Green/Red" that is hooked to nothing is likely your problem. It should be hooked to switched 12V power as Rich's image indicate. Lookup Ford 2G alternator wiring, you'll find lots of images that may help. The RF harness should have a brown wire for this purpose.

[Avalanche325]

Aren't to 2Gs a bit of a fire hazard? There was a lot going around about this a few years back.
I would go to a 3G.

[rich grsc]

Yes, and no. The fire issue was with old and corroded connectors, but I too would go with a 3g. Smaller and better output for the same $$$. A small case 3g is perfect.

[lenleg]

Yes, and no. The fire issue was with old and corroded connectors, but I too would go with a 3g. Smaller and better output for the same $$$. A small case 3g is perfect.

Thanks everyone. Got the problem solved. Also spoke to Johnny and Jeff over at Whitby and even though I got the wiring straightened out .... I will upgrade to 3G. They told me about the fire hazard and poor output of this alternator.