1998 tahoe AC Question, Did a search, could not find what I was looking for

[1991SSP]

I am using a PSI harness with programmed 411 pcm... I was looking over the pinouts on the original pcm and noticed the AC system controls run thru the old pcm. I have removed it and plan to mount my new pcm in it's place..... How do I keep the AC system functional,,, I am re using my original compressor on my new 5.3 so everything else in the AC system is still in it's original layout.........


Also, which wire under the hood is a good source for 12 IGN/Crank/Run

[gagliano7]

I used my original a/c on my 1992. Does a 1998 use a distributor? i used the hot wire going to the dist for my 12v ign/crank/run.

[Mickeymotormount]

You may get lucky and have proper pinouts on the new pcm. It would be a question of knowing which ones, what they do and running the wires accordingly.

Here are some manuals with wiring diagrams that are always helpful. I consider the cost of the manuals as part of the overall job.

http://www.ebay.com/itm/1998-Chevy-S...d26406&vxp=mtr



http://www.ebay.com/itm/1998-SIERRA-...4cbd70&vxp=mtr

http://www.ebay.com/itm/1998-Chevrol...8af774&vxp=mtr

http://www.ebay.com/itm/1998-Chevy-S...17cb1d&vxp=mtr