1997 Audi Cabriolet Fans not coming on!

Is it possible that if my thermostat is stuck, could this cause the fans to not come on. If so, where is the thermostat physically located as I do not have a manual for the car. I checked all the fuses and they are good. If it is a relay that possibley failed where that coils of the relay is opened, which relay number(s) are they.

Thanks for your help,
Lance