View Full Version : 89 C1500 HVAC: two questions


Engine-Ear
01-10-2007, 01:14 PM
hi everyone, my '89 Cheyenne has 198k miles on it and I have had everything except the ducts and the electronic head to control the heat and A/C replaced. The animated controller has a mind of its own and I am tired of having A/C blowing at my feet when I want it at my face or having nonfunctional defrosters despite the fact that the is control is showing me a picture of A/C-enhanced defrosting.

I read thru the previous 8 pages of the threads and came up with the likely culprit: the dash controller itself. Does anyone know the OEM p/n? (A used one will probably do the same thing sooner than later) Should I be looking for any other likely culprits?

Another issue is a major airleak around the heater/AC box at the firewall...I suspect that the place that did the A/C work omitted the gasket (or didn't replace a rotten gasket). It isn't practical on many levels to bring the truck back to them to fix it. Is regasketing the a/c box a b!tch for a novice?

Also, are OBS and NBS short for Old Body Style and New Body Style, respectively? What are the year ranges for these terms?

jgj5150
01-11-2007, 04:10 AM
Hey, these controllers can be had off of ebay for less than 10 bucks. I would consider trying a different one of these controllers before I tore into anything else...

Just search for 88-98 car truck parts...

Jason..

Engine-Ear
01-19-2007, 11:57 AM
thanks, jgj5150, I wil look into it.

when the weather warms up I will pull out the controller and see if there are any melted wires, circuit traces, etc. on the existing unit.

Another issue is a major airleak around the heater/AC box at the firewall...I suspect that the place that did the A/C work omitted the gasket (or didn't replace a rotten gasket). It isn't practical on many levels to bring the truck back to them to fix it. Is regasketing the a/c box a b!tch for a novice?

Also, are OBS and NBS short for Old Body Style and New Body Style, respectively? What are the year ranges for these terms?