ok ive seen this in here before but cant find it. I have a tuned pcm comming its from an 02, now i have a 99 pcm the truck is a 99. so now what do i need to do for the alternator? and does anyone know the gm part # and how to hook up the wires. which wire to pcm? blah blah blah.do i need a 02 alt harness? and i know i need a crank relearn thats no prob. thanks guys.

 

I have a 02 PCM in my 00 and didn't do anything but the crank relearn.

 

who ever is doing your tune with that pcm...just have them turn that code off. You don't need the wire. Won't hurt anything.

 

Yep L-term set to no code.

 

I sold the tuned PCM to Mason so its already on its way. It was tuned by TSP. Dam I should have mentioned that to TSP when they had it, I forgot all about that

Hey Mason, I have the alternator clip and got a wire with the pin for the PCM harness if you want them. I never got around to putting them in. Hows $5 for the harness and wire shipped?

I remember reading that somebody did the wire trick but it did not fix the blinking light, they ended up getting a newer alternator and that took care of it.

 

i added the the wire to no avail, i had a newer alternator lying around and it did the trick. seems to be hit or miss on whether the added wire works or not.

 

Good to know.

 

The wire didn't work for me either, I had to install a newer alternator along with the wire to turn off my blinking battery light. I took the opportunity to upgrade to a 145amp alternator at that point. I got a new factory take-off for about $100 from G&R Auto Parts. Had to install a longer belt for the alternator also...here's some more info for ya...

https://www.performancetrucks.net/fo...+official+2005

 

You need to turn off both of the codes, P1637(Generator L-terminal circuit), and P1638(Generator F-terminal circuit). That will take care of all codes and the light for you. Make sure you disable the SES light for both and set the codes to "No error reported". If you just set it to no ses light the battery light will still blink in your DIC.

Chris

 

I have a spare 105a alternator off of my '03 (under 30,000 miles) that I'd part with, PM if anyone is interested