SL 380 Auto Climate Control - PeachParts Mercedes-Benz Forum

Ray380 · #1 10-10-2007, 02:11 PM

I have a 1985 SL 380 with A/C problems. The compressor is new and so is the pressure switch and filter. At times the air conditioning works fine but after about 10 minutes the air cuts off and nothing comes out of the vents. If I switch to the economy setting (or any other setting) I still get nothing. After a period of time say 10 to 30 minutes the blower starts to work again.

Any suggestions would be greatly appreciated

Thanks

Ray380

ctaylor738 · #2 10-10-2007, 04:29 PM

If you go to DEF does the fan work?

tecqboy · #3 10-10-2007, 06:00 PM

Sounds like it's icing up. Possibly drains blocked? Do a forum search as there is lots of info AC.

Ray380 · #4 10-10-2007, 06:27 PM

Quote:

Originally Posted by ctaylor738

If you go to DEF does the fan work?

What is DEF?

The fan works works when the A/c is OK. The problem occurs when the fan goes off.

Ray

nobby · #5 10-10-2007, 11:17 PM

Quote:

Originally Posted by Ray380

What is DEF? Ray

DEFROST

ctaylor738 · #6 10-11-2007, 07:38 AM

Sorry. DEF/Defrost is the button on the left. I forgot that it has the little icon on the newer push-buttons. In Defrost, you get air from the side and windshield vents and the highest fan speed.

The reason I ask, is because the fan is "hard-wired" in Defrost. If the fan does not work in this mode, then you most likely have a problem with the fan itself, or maybe the fan relay, which is right behind the glove box.

But if the fan does work in Defrost, then I would look at vacuum issues like a leak somewhere. This is because there are a couple of vacuum-actuated switches that need to be closed before the fan will come on.

Ray380 · #7 10-15-2007, 07:06 AM

Quote:

Originally Posted by ctaylor738

Sorry. DEF/Defrost is the button on the left. I forgot that it has the little icon on the newer push-buttons. In Defrost, you get air from the side and windshield vents and the highest fan speed.

The reason I ask, is because the fan is "hard-wired" in Defrost. If the fan does not work in this mode, then you most likely have a problem with the fan itself, or maybe the fan relay, which is right behind the glove box.

But if the fan does work in Defrost, then I would look at vacuum issues like a leak somewhere. This is because there are a couple of vacuum-actuated switches that need to be closed before the fan will come on.

The defrost does not work when the A/C has switched itself off. Niether does the any of the other buttons or any of the fan switches.

From your description it appears that I should look at the fan or relay.

Thank you for your help.

Ray