M.B. Doc,
Thanks for the response. My problem is that when you push the "hi" button, there is no increase in fan speed like my '87 300E. Yes, I have a normal fan speed when I first start the system. In the 300 E if I push "Hi" then the speed substantially increases. Not so with the E420. I don't know if I have a problem, maybe a design change?
Anziani