This is the electronic control unit for the BMW Climate Control system. 6411-8 390 122.4  This unit also controls some other components too.

This unit was removed from a recent crash damaged 1994 525i - this is offered with a 30 day warranty!

Easy to install and instructions are available for the do-it-yourselfer.

Typical symptoms include: A/C - Heater blower will only run in the "MAX" position or continues to run even in the "OFF" position. It can also result in the loss of one or more fan speeds, or an nonoperational climate control unit, or a center control selector that won't work.

Check your original part number to verify fitment.
 

 I only sell the OEM units, never aftermarket so they are the same quality as your original. Thanks for looking!