AC relay?

[OlSmokie]

The AC in my 1990 C1500 quit working on the weekend. I thought maybe it just needed charging so I bought a can of Redtek to charge it but the pressure was good. The compressor was not cycling so I jumped the switch on the canister and the clutch kicked in and the air started to get cold. The fan works fine too. This led me to think it is either the switch on the canister or the relay. Is there anything else that might control the air compressor? The switch is right there, but where is the relay located?
Thanks for your help on this.

 

[jdyates]

Exact same problem on mine. I rigged it up to the fuel pump fuse to come on with the ignition. Otherwise the A/C wouldnt work. But the fan is always on now.

 

[1997chevydriver]

It's probably the low pressure switch that went bad. I had it happen on my 94

 

[jdyates]

It's probably the low pressure switch that went bad. I had it happen on my 94

Is that the plug on the top right of the condenser?

 

[1997chevydriver]

Is that the plug on the top right of the condenser?

Usually is on the dryer (silver canister on fire wall)

 

[OlSmokie]

It's probably the low pressure switch that went bad. I had it happen on my 94

Will I lose my charge replacing it?

 

[1997chevydriver]

Will I lose my charge replacing it?

No. It looks like you will due to how its screwed in but there is a little check ball in there.

Sent from somewhere in Minnesota using Tapatalk 4 Beta

 

[jdyates]

Gonna try replacing mine, then. Thanks paul!

 

[great white]

Agree, low pressure switch.

Common failure point.

Changeable with no pressure loss due to aforementioned check ball.

 

[OlSmokie]

I have it fixed. My low pressure switch in on the compressor. The switch on the canister on mine is called a compressor cycling switch. I took it off and cleaned it out. I made sure the contacts were clean and re installed it. It is blowing a steady 47f now.