W 140 Air Conditioner -weak blowing, then quit
 

My 1995 Mercedes W 140 mercedes (S320) had been experiencing less than stellar air flow from the A/C, even on max air. I bought it new so I know what is was supposed to do, but the decline in air volume has been slowly deteriorating. It gradually got weaker and weaker although it was still cold. Yesterday, it quit blowing at all. Any ideas?

Check the fuse link on the driver side strut tower.

If the air volume has decreased , but the fan speed has not, you want to change the cabin filters.

If the motor has decreased in speed, you want to check the brushs/bearings and regulator.

What have you checked??

The links should help you understand, probably the regulator, if the motor spins by hand
http://www.peachparts.com/Wikka/W140BlowerMotor
http://v12uberalles.com/pollen_filter.htm

Early 210's use a very similar regulator (same electronics, different wiring harness) and this is a very common problem.

It usually first presents itself as a blower that works fine up to half-speed, then will blow no harder.

Apply full power to your fan motor by disconnecting the regulator and grounding the motor lead that went there. The other lead is battery voltage. If the motor runs at full speed, it is fine and the fault is almost certainly in your regulator.

There is a slight chance that the fault is in your pushbutton control module, but that chance is very, very slight.

Going through the PO's old receipts, the regulator on my W210 was replaced under warranty due to the same issue. New regulator fixed it.

That was an excellent DIY article at the link. At a minimum I can show it to a local tech. Small town mechanics around here tend to shy away from anything not a Ford or Chevy, so this is a big aid. At best I can tackle the job myself. Thanks.