1983 Cadillac Coupe Deville climate control lights not working not coming on or doing anything. Blower stays on high. Antenna does not work as well. Checked fuses. Does anyone know which fuse or relay and where it's located. Pictures or vid would be helpful. Mecanic says might be module? But no lights or anything.

 

If you press Off and Wamer button for 3-5 seconds does anything light up on control head. If so the Programmer would be my guess. The ATC fuse is in the main fuse block. The blower is controlled by Blower Power Module out on the evaporator case. The Programmer is behind the glove box. blower stuck on high can be a default of climate control fault or the Power module. Key should be off plugging and unplugging power module. It is voltage spike sensitive.

Power antenna normally are unplugged for because they run all the time. Is there 12v to antenna connector?

80-85 Cadillacs have a lot of Cadillac only electronics including the DFI. You really need to invest in Factory Service Manual ,for the model you have, to repair and maintain. You can bring with car for service just be sure to get it back afterwards. If you are a repair shop encourage car owner to provide it or I guess it could be shop supplies.