Hello, fellow 300 owners, blower failure seems fairly common; had this problem last year, pulled out the fan, tested with good battery, and all seemed well. Now, no blower fan situation is back.
Surprising to me, if I hit the passenger side by the transmission tunnel, the fan will usually start to blow, leading me to think it's external fan related; relay, blower resistor, or blower control module. Once the fan is blowing, I can increase and decrease the fan speed witht the fan buttons. If I turn off the fan, can't turn it on without the sides again.
Any advice on this? Thanks in advance!