Jaguar Repair: fuel shut off valve, climate control system, vacuum switches

Question
QUESTION: mr howard  my tamp ctl// stop working on 85 xj6 no air just heat i got 2 more temp switches they only work on heat could it be any thing else that controle ac i have change relay pak// and amperfire check temp controle with ome meter thay check good.

ANSWER: Hi James,
Sorry, I can not diagnose an AC system via e-mail as the test sequence is seven pages long. You need the AC / Heat manual form Jaguar to diagnose an AC problem.
Howard

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QUESTION: mr howard what controle fire going to shotoff valve on 85 xj6 jag

Answer
James, you will have to explain what shut off valve you are talking about. If you mean the heater control valve. It is not electric, it is vacuum controlled by vacuum switches on the control drum (servo assembly). Then if you are going to ask me what controls the drum, It is controlled by a small electric motor and it is controlled by, The mode control switches, a in-car temp sensor, an ambient temp sensor, a water temp thermistor, a temp selector, an amplifier and a feed back potentiometer.

I have been working on Jaguars a long time and I can not fix a climate control system without my Heat/AC book open to refer to. If you can, great. You should go into business doing that. And sign up in this program so we can direct all Heat/AC questions to you.

Sorry James,I can not help you with your climate control system, get the manual.

Howard