Another AC Question - PeachParts Mercedes-Benz Forum

kwintoz · #1 08-13-2008, 01:00 AM

As if there isn't enough questions on this already,I will add a couple more and hopefully someone can help as I am getting very frustated with my AC!I have a 1995 C220,AC compressor would run for a few seconds and seem to stall out.You can see it slowing down and dragging the engine down before the clutch would kick out.It would then try again,same thing ,then go into EC mode.Had the system evacuated and recharged by an indie who also replaced AC pressure switch[ I don't think there was anything wrong with the old one].I soon got a feeling that this guy didn't know much about Mercedes.Anyways it is still doing the same thing,took it back and he says"probably needs a compressor",well probably isn't what I want to here when I am paying the bill!Now,when the compressor is cold,you can turn it over fairly easy by hand.When it is hot,you can only turn it a couple of turns,it gets harder as you turn it more,until it won't turn anymore.I also noticed that the auxillary fans don't come on when the compressor kicks in either but they work if I jumper out the relay.Does this sound like a compressor on it's way out or could it be something else?Should the auxillary fans come on as soon as the compressor kicks in and if they are not,would that have any thing to do with the compressor stalling out?Enough for now.Any help would be appreciated.TIA

mbdoc · #2 08-13-2008, 08:00 AM

That car has "belt slippage" protection built into the a/c controller.

Testing for that problem can be done at the compressor.

The comptessor needs to be operating & then the speed sensor output measured.

Sounds like the compressor is the problem.

kwintoz · #3 08-13-2008, 01:04 PM

Thanks for your reply MB Doc.Could it be possible that something is plugged and causing the compressor to pressure up and stall out or do you think that the problem is the compressor itself?Is there any way to test the compressor by itself?
Thanks