A/C CLIMATE CONTROL UNIT PROBLEM OR MORE

You probably got low refrigerant... it would never let you run AC if your refrigerant is low. Make sure all the wires at the A/C drier is hooked up... front driver side next to radiator... round cylinder thing... behind headlight.

I suggest you take the fuse out and replace it for the flasher... it is usually the fuse... it look deceptive when in place. I never changed any flasher on MB... it is not like US cars that flasher goes bad.

Low refrigerant would account for the compressor not running, but what about the blower? He says that doesn't run either. Does anything work? How about heat?

Blower is also due to age of the car... They usually crap out at about 16 years old. Not bad for original blower motor...

I would check freon level... change all the fuse related and then diagnose further.

Why should he be looking at freon, when the blower doesn't even run and there is nothing working? The blower should run without the compressor starting. It should also run to supply heat. Apparently none of that is happening, so I wouldn't be worried about refrigerant level at the moment, as at a minimum something else is wrong. And whatever it is, that may be all that is wrong.

I'm glad to see somebody is thinking.

Put 12V and GND to the fan/blower connector. If it spins, it's good and there's a 99% chance your pushbutton switch asembly is bad. That seems to be the bit that always fails. They're like $300 rebuilt, don't even ask about new ones but you can usually get a working good one for about $50 off flea-bay or a wrecking yard. try car-part.com for wrecking yards.

The defrost setting is the benchmark. It should rnu full fan and full heat, period. It that doesn't work the pushbutton assembly itself is always the first thing to check. No power getting to the far on defrost is an almost sure sign the pushbutton assembly needs replacing.