Hi All,

The A/C in my Volvo 850 GLT works for sometime, then automatically shuts off. It always works right after we start the car and go. It usually does not work for longer periods of time when it is extremely hot outside (which is when we need it the most). I know there is a thermal/pressure switch that regulates the compressor. I suspect that this switch is shutting the compressor off after a certain temperature threshold is reached. Assuming this is the issue, Is there a way to bypass this switch?Any other ideas why this mightbe happening and any remedies to getaround it? Any help will be greatlyappreciated.

Thanks,
Shakil

 

I think you'll find that your compressor clutch gap is too large. Check out Tech's post here on how to fix it (https://volvoforums.com/m_34431/tm.htm). One guy on here even did this successfully recently without removing the compressor!

I didn't see that post and changed my compressor and it fixed the problem too. It would have been a lot cheaper if I'd seen his post first.

Also, there are two switches, a low pressure and high pressure switch. You can jump the switches by disconnecting the electrical connection and using a paper clip (or some other wire) to jump the two leads. The low pressure switch actually has three leads, so I'm not sure which to jump. However, based on a number of threads on here, the problem is most likely that the clutch needs reshimming.

Good luck!

 

+1.

Hi Shakil,

The A/C compressor on 850 is really a fiasco (and it's made in Japan[8D]). BTW, in case if re-shimming does not do, it may be the pressure switch or the evaporator. If the evaporator is of original, it may be time for a new one, Tech has a post on how to, but expect this to be one of the longest repair procedure, as most of the dash has to come out (it seems to take Tech 3 hours to do one). But if you do not find a leak, the evaporator is probably fine.

And don't forget, there is always Duct Tape at your rescue.

Good luck,


Kanji/JPN

 

Thanks for the great advice on the A/C guys. Will check it out tonite. Take care.

-GLTOwner