Nothing on 1990 Audi 100 Quattro

My car has a fan roblem

Asked by for the 1990 Audi 100 Quattro
The fan to cool the engine is mounted on the radiator, it is electric and is "turned on" by the electro-thermo switch mounted also on the radiator. What is the problem with your fan or is the car simply over heating. Many other things can cause a cooling system to over heat.