TheSaint

I was out driving yesterday and since it is winter i was turning down the blower motor fan speed from speed 3 to speed 2 and then all of a sudden the blower motor started working at maximum speed and the speed stays at max speed even if i turn the bllower motor speed off

I suppose that this is the blower motor regulator which i replaced with a brand new one for about 16 months ago that is broken again?

I replaced the blower regulator with a brand new one(if i had only used an original Mercedes regulator and not a regulator from ebay)i suppose this would not have happened

There is one thing i find strange and that is that the blower motor works at maximum speed since i thought if the regulator broke the fan speed would be zero?

Any of my fellow members here on the forum that have had a blower regulator break and still have the fan blowing at full speed?

Any innputs about what the problem might be if you do not think it is the regulator is broken is more than welcome

Plutoe

The AC control module is responsible for sending the voltage message to the regulator and adjust the fan speed!!