Climate Control Problems

In my e34 1990 535i, the climate control is confusing. For starters, in between the center console vents, there is a vertical dial labeled red on one end and blue on the other. I can't fugure out what it's supposed to do but am guessing that it's not working as it never seems to change anything. Can anyone give a quick lesson?

Secondly, though, it's a choice of very cold with A/C or very hot in my car. I can never get cold air out of the defrost or floor vents no matter what I do, A/C on or off. I'm guessing that the diverter for the heater core is no longer working well and is always on now. Does this sound like a good guess and is this a common problem? :banghead:

the dial in the vent is for 'stratified air' mixing and should allow you to have differnt temps between the floor and the center outlets. the 'hot or a/c cold' problem sounds like a bad hot water valve.....it's in the L/R corner of the engine bay, mounted with the aux. water pump, under a small black cover.

Explain the "stratified air mixing" again--? I thought that's what the three sliders were for. Exactly how does the temperature difference factor in? I bought a 1990 535i a month ago, and my old '86 528e (which I understood fine) did not have that feature.

'bmw's ' idea is that you basically set the floor temp. you want and by rolling that vent dial up or down, you'll vary the air temp. coming out the vents when you open them [e.i. hot feet, cool face, upper body], this being an old BMW design to keep the driver comfortable and AWAKE on long trips I think, or they claimed - it's worked for me. jb.

OK, thanks. Still sounds kind of wierd, but it's summer now and there's been no chance to use the heat (bought the car end of April).

With my 528e, you just moved the middle slider back and forth to let outside air in (plus it made a cool hydraulic sound as the vents gradually opened or closed). That did work really well! I doubt there's been any other manufacturer that allows that kind of "temperature stratification" conducive to alert driving. I miss the automatic climate control of my Legend LS, but BMW's all-business attitude is again evident even in their HVAC design.

Aside from a brief ride in a '97 M3, my 1990 is newest BMW I've been in. I know the newer ones have automatic climate control, but do they still allow the same control over various air temperatures?

tes they do and, your '90 basically has auto/climate as did your 528e.....auto means an in-car temp sensor and a means of auto temp control which except for the E30's, all BMW's have had since '82.

Thanks for that explanation. I know the temp dials have the little numbers on them, but I never took their ability to actively maintain a temperature very seriously. My Acura (and my parents' '87 Audi 5000) had a digital readout for temperature, and the climate control on both would invoke even the A/C if necessary.

I will give this another shot with my 535--didn't know there was actually an in-car temp. sensor.

A few years ago I was reading a C/D comparo (must have been 2001) and they were complaining that although their 740iL had automatic control (including digital readouts), the fan speed still had to be adjusted manually. I guess BMW has always taken a different route than everybody else with respect to climate control.

the temp you set is really just a range the system will keep it in. The 740i's if set on 'auto' will control fan speed also. BMW did take a different tack on many controls, chosing, i guess, giving the driver priority over systems, which was great but now they've gone somewhere else.......I-DRIVE! a-h-h-h!

Yeah, with the current line of BMW's (excepting the 3-Series), the company has abandoned a lot of cues that have existed through decades. I sat in the new 5 and 7 Series sedans at an auto show this past winter, and even the trademark dash with the center stack canted toward the driver and the sort of "arched" dash in front of the passenger has been done away with. I guess it's tough for a company to maintain an individuality that has its roots 30+ years ago (as it pertains to modern BMW's) in the face of ever-modernizing competition. BMW took a daring leap forward in technology (from what I hear, read and see) and only half-heartedly hung onto traditional identity.

Since I'm of modest means :rolleyes: , I'll at least have a few generations of traditional Bimmers to enjoy before I have to worry about buying one of today's models!

I couldn't agree with you more! One of my sorriest days was when i had to go to LA to the new model intro. for the E38's in '95 for techs. and some of more experienced technicians almost cried when we saw the e-brake moved to the floor and the electrically 'assisted' trunk closure. it was the end of an era. 'twas the beginning of the 'bangle' saga.

I understand--but still think the E38's are very nice looking cars. In my opinion, BMW's styling pinnacle was reached with the E36, E38 and E39 (but I'm also too young to remember vividly when the '80's BMW's were brand-new). The 1980's and earlier Bimmers are sharp-looking but a bit too stodgy, and the 2002+ ones are...well...