Hey everyone I just wanted to than you for the add, and wanted to introduce myself/past a problem I'm having. Stationed at Ellsworth afb in SD, been here two years, own an 89 f150 that I'm fixing up for winter endeavors.
So I just got back from deployment and wanted to work on the truck again, it wouldn't start last summer and thought I had it narrowed down to what the problem was. Figured it was the ignition control module mounted to the distributor. Only one if the mounting holes had viable threads to month the ICM so it wasn't making good contact. Purchased new distributor assembly (came with new rotor, cap, ICM etc) and sure enough it fired right up and continued running.
As it was running it still had low voltage (discovered that when it was running last year). I let the truck run for a good got minute until it got to temperate and it still wasn't charging. Decided to pull the battery and the alternator to get them both tested/charged. I go to pull the alternator and the first thing I see is I'm missing a wire. i know I'm going to get made fun of hardcore for this, but apparently when I swapped it last year, I forgot to splice in that other wire. I purchased the new plug just yesterday, and just need to splice it in.
My question for you ladies and gentlemen, is where do I splice the wires? It's the voltage regulator that sits on the top of the alternator, and splices into the other rectangular plug that is on the bottom left, and eventually plugs into the starter relay. Thanks in advance!!!

 

I'd post a picture or at least tell what color the wire is. There's more than one. Not really clear why you had to splice wires, it should have been just a bolt-in/plug-in.

 

The replacement alternator came with a new rectangular plug that I spliced into the old wire. The wire I need to splice in has a yellow w/white stripe, white w/black stripe, and green w/red stripe.

 

Welcome to the forum. Glad to have you join.

 

Welcome to the F-150 forum! Glad to have you join us.