smp928s

My climate control is a mess on my 87 5k, no matter what setting i set it at it seems to blow out hot air to the defrost vents and the floor vents. I cannot get it to shoot out of the dash vents no matter what i do. I have no idea the condition of the ac system but when i set it to the coolest setting it sounds like the ac compressor is coming on(the engine works a little harder). If anyone has any suggestions I would greatly appreciate it!

ARK

display unit. The "controller" is buried somewhere under the dash, and takes the electrical signals from the display unit and controls the vacum operated air flaps. The controller contains a bunch of solinoid vacum valves. It is a POS General Motors unit, they all fail eventually.

Bonz

the bently manual i own states that when the AC has a vacum leak by default it goes to maximum defrost. you should check all your vacum lines, you can start by checking under neith the big plastic auid thing you see when you open your hood then try unneith your glove box and check the programer unit

Trex

Is there a cheap GM replacement unit available? I think my 1986 5000 S needs a new controller/head unit and I've see a $500.00 price tag on it. Know of anyplace that sells them at a good ( better? ) price? Thanks.