seat heating control
 

Can anyone tell me how the seat heater control works and/or especially what pins on the switch control what function? This is for a '97 A6 Quattro. My guess is that the rather sophisticated looking circuit board inside the switch controls the temperature. I'm also guessing that one pin receives +12VDC with ignition, one is ground, one is for power for the illuminating light, one or two pins somehow control a relay and another pin would be connected to a variable resistor used for thermal feedback. I know that's roughly how BMW does it. Thanks for your ideas!