BMW Repair: HVAC acting up, climate control unit, bmw 328is

Question
Hello,
For a few months, the HVAC system (it's digital in the '96 BMW 328is) has been cutting on and off intermittantly,  seems worse when it's colder (of course).  Sometimes when it's on, I cant change the setting to 'Auto' from  one of the other 'vent' settings. Today it's on, but it's not blowing heat, just cold air.  It went off once when I hit the surrounding cowl, but I couldn't turn it on that way.  I also notice that the right side of the radio display sometimes dims (this predates the heat problem)  I have a Bentley manual and tools, but I don't want to rip and tear randomly.  Any ideas?

Answer
Try this, find a junk yard and try to buy a climate control unit.  if it's not switching vents and you can't control the temp then that's most likley the problem.  i've seen quite a few bmw's where the lcd display on the radio goes dim or a few figures are missing and that's when they need to be changed because they can't be fixed.  Try e-bay, you migh be able to find one cheap there.