Hello
My air conditioning doesn't work. When I press AC there is no power coming to the compressor solenoid. (It pulls bridging with 12V)
Is there a fuse for this? Or a relay?
Chevrolet pickup K1500 built in 1989

 

Are you sure the system has a proper charge? There is a low pressure switch to prevent the compressor clutch from engaging if there is insufficient coolant in the system. There is also usually a high pressure switch to prevent operation if there is too much coolant in the system as well. I am not sure if there is a relay, but you probably need to start by putting gauges on the system.

A 1989 K1500 would likely have still been built using R-12, which is no longer available, but there are likely R-12 alternates available these days that may actually work in such a system. You will need R-12 gauges for working with it unless it's erealready gone through a conversion to R-134a or another refrigerant.

Here is a link to manuals and diagrams for a 1989 K1500 - not sure if you have the 5.7L (350), but they have the other size engines on there:

https://charm.li/Chevy%20Truck/1989/...V8-350%205.7L/