I have a '93 300SE that has a blower motor that stays on after turning off the key.........runs untill the battery is dead............is this the controller or the blower regulator? Both expensive, hate to guess.

I don't have advice for you but my SD drains the battery over a couple of days. I've checked a number of systems with the convenience module being the prime suspect at this time. I haven't checked the blower motor but that's next.

Sixto
93 300SD