My heater fan stoped working out of no where. I turned it off and the next day it would not work anymore.
Sounds like a fuse, usually they go slower and make a groan noise when they're about to kick over., Mine still blows a bit, but with a groan. Here's a link on how to remove the blower motor/fan. http://www.justanswer.com/mercedes/4dzh6-mercedes-benz-190-e-blower-motor-fan-blow-fuse-190.html You'd be a lucky man if it turned out to just be a fuse. (fuses driver side all labelled) Basically removing the wiper, digging into the blower area. With mine I'm only going to be able to spray it with white grease - can't afford more than that at the moment:)
Join the fan blower replacement club. They ALL break without warning. If your switch knob is stuck in a position - you need to replace the unit. About $125+...there's no other option.
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