AC Functions Sporadically -- 94' S500
 

I must confess that I'm not a car wizard. But I have been able to research just enough on the internet to get me into trouble. :D

Here's the problem... My AC tends to work just great when I first start up the car and the car is cold. The blower motor provides ample air supply and the temperature seems to be cool. However, the air flow (volume of air) starts to diminish after 15-20 minutes. The air still remains relatively cold...but it seems to trickle out of the vents. I checked the filter and it was clean. When I checked on the blower motor, it seemed to react properly when adjusting the speed from Low to Auto and Max. (The car had cooled while I got all the covers removed...so I don't know if that plays into the equation or not)

I've found a couple of sites with posts that say it may be the "blower motor voltage regulator." Would this be the case? Any other ideas? Is the "blower motor voltage regulator" on top of the blower motor? Is that the same as the "blower motor resistor/regulator"?

Just in case Sleepwalker asks... WDBGA51E7RA175404 Appreciate the help.