I have a 1986 SL560 - my A/C and auxillary fan has stopped working.
Before the A/C stopped working completely, the cool air came only from the side vents - the center vents did not work at all. Just recently, even the auxillary fan stopped working. I have checked the fuses - all are o.k. Is there a way I can check the grounds to make sure everything is grounded properly?
I have located the relays - I still can't find the auxillary fan preresistor? Can you offer any suggestions? What does it look like?
Would appreciate any help you can offer.

TZ