A/C thermostadt switch
 

I have been working on my 85 911 A/C and it is charged and ready to go but the thermostat switch on the left of the blower switch does not seem to engage or disengage. I know where the A/C fuze is and the Blower relay is but is there a separate fuze or relay for the thermostat switch? Thank you, Nick

Thermostat switch
 

there is a relay is in the smuggler box attached to the wall on the co driver side...

Fuse #2 is the A/C switch.

Check for voltage on both sides of the fuse.

Let's hope that the capillary tube has not been damaged.

Good luck,

Gerry

The contacts inside the thermostat can get a bit corroded and prevent it from working. An easy diagnosis is to bypass the switch by jumpering the 2 leads to it. If that turns on your compressor then you know the switch is your problem.

If the capillary was damaged as Gerry said then your switch is toast and you need a new one. If it's just dirty contacts they can be cleaned to fix the switch.

nick,
go to these links on subject;
http://forums.pelicanparts.com/porsche-911-technical-forum/851829-c-wiring-questions.html#post8489066

http://forums.pelicanparts.com/porsche-911-technical-forum/848870-ac-switch-only-full-setting-works.html#post8458139

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Thanks!