'87 AC Temp Switch Diagnostics

[llangston1]

I am trying to check out my AC temp switch according to the write up on Griffiths web site. I got access to the switch and connected my ohm meter across the spade terminals and I read "0" no matter where the switch is positioned. Fully CCW or anywhere in between I get a zero reading. And yes I did check my meter to see if it was working correctly. The AC was cooling but I was getting lots of evaporator ice ups. I checked the temp switch with a cup of ice and when the capillary tube in is the ice it will disengage the compressor clutch but turning the temp switch fully CCW seems to have no effect on the compressor clutch. Do I need a new switch? It does not look that old. Attached are some pics of the switch. Is my switch a different design that does not cut off the compressor at the full CCW position? Someone had wrapped some prestite tape around the capillary tube where it comes out of the switch. Is that normal? Needless to say I am a little confused. Any suggestions on how to proceed?

[llangston1]

Here are the pictures of the switch

[86 911 Targa]

Originally Posted by llangston1

I am trying to check out my AC temp switch according to the write up on Griffiths web site. I got access to the switch and connected my ohm meter across the spade terminals and I read "0" no matter where the switch is positioned. Fully CCW or anywhere in between I get a zero reading. And yes I did check my meter to see if it was working correctly. The AC was cooling but I was getting lots of evaporator ice ups. I checked the temp switch with a cup of ice and when the capillary tube in is the ice it will disengage the compressor clutch but turning the temp switch fully CCW seems to have no effect on the compressor clutch. Do I need a new switch? It does not look that old. Attached are some pics of the switch. Is my switch a different design that does not cut off the compressor at the full CCW position? Someone had wrapped some prestite tape around the capillary tube where it comes out of the switch. Is that normal? Needless to say I am a little confused. Any suggestions on how to proceed?

Is this your switch?

[llangston1]

Maybe 3rd time is the charm for pictures of the switch

[llangston1]

Pictures of my switch

[Bob Kontak]

Here is a thread talking about freezing up. Biggest culprits are lack of refrigerant or not enough airflow over evaporator per one post.

Evaporator froze up again.