heater motor wont shut off 2002 clk320
 

Sorry it a 2000 not 2003 I am posting this for my brother I am an X machanic of 9 years working on BMW volvo mercedes and sabb so I know more then the basics.
The fan motor will not shut off I know there is a rest button that can turn the fetaure on or off but it does not help the only way can we shut it off is by pulling the fuse. He took the car to the dealer they said it could be 3 things so to me they are chasing the problem.
1 the blower motor
2 blower regulator
3 the control pad on the dash is bad
ALL PROBLEMS COME TO A 1,000.00 TO FIX.......

Almost always the blower regulator! START there.

Blower regulator
 

I changed mine this weekend, it took 30 min it's all set and working. Total cost 98.50.. Dealer wanted 800.00