I installed high speed fan switch like this one in pics except I use ground to pin #17 like somebody from here told me, but last months conectors are burn out on groung (black wire) on fan ,I get new conectors from FOrd dealer, and 2 weeks after (tonyght ) same thing,
Why groung on fan getting too hot
Why groung on fan getting too hot
How often is your switch on and running the fan on high? 