Odd wiring issue, 8v on my alt

[norville]

Hey all, I'm almost done with this mess, the PO road killed the heck out of LS swap on this truck. It's an 86 scottsdal with only 80k on it and AC and Ps/pb.

I almost have all of the messed up witing figured out but I'm having a battery drain issue. While sitting I have about a 500mA draw, I figured out that it's the single wire going to my alternator. If i pull the alternator wire out trigger wire, the draw drops down to 5mA..Somewhere along my harness voltage is getting back fed into that line...

Key off wires to my fuel pump and crank circuits are correct, I don't think it's my ignition.

Unplugging the cpu fixes the issue also..lol

This is an ebay special harness, I found one lead as to the issue on LX swap forum, but I'm hoping someone here has also had an issue like mine.


Thanks,
Bob

[norville]

Am I wrong in thinking I'm off one pin? The white wire has 12v key on ..

Never mind this is correct, pin 76 is for the injector.

I've seen 2 different pin out schematics, one says 75 is not used and another says it need 12v key on??? I don't think this has anything to do with my problem. I think either the pcm is bad or I have a crossed wire in my harness..

[norville]

While it's disappointing that I will not be able to use the CPU to control my alt. I've decided to just bypass the cpu and run Acc 12V with a 470ohm resister directly to my alt. I'll use two wires so the alt can sense vehicle load.