Mercedes ML 500 W 163 radiator fan replacement 

I agree but these are also cores that the auto part store wants returned, reason why I didn’t take it apart

There are two switches that turn the fan on: a hot temperature switch in the cooling system of the engine, and a pressure switch in your air conditioning system. Both of those turn the fan on. It’s a harder one to reach. There are other video on the net to see where it is.

Please, if you haven’t already, consider subscribing. It will be of great help in the continued effort to make content for this channel. Thank you