Unofficialbmw.com

[jonesygrl]

HAA HAA....The weirdest thing happened tonight! I was driving home...no weird weather, no weird bumb in the road...and my air (digital climate control) just turned itself off. Barely time to notice it, and it turned back on (so then I thought I was just on crack). But a couple of minutes later, it turned off again...and this time, it wouldn't start again. I pushed every button I could and NOTHING. The only thing that did anything was changing the cold/hot air nob on top: doing that made either freezing cold air or SUPER hot air come out (at about medium speed- which it wasn't at when on). Then all of a sudden, it just turned right back on as if nothing had happened!
What the heck? I read past posts about connectors being bad or ground wires...anybody know if this is the same problem? Anyone got a fix?
Watch...it'll probably never happen again, though!

[RPR]

Some bad news for you Arianna... Your problem will happen again & again. The entire IHKA (digital control panel) is failing. The blast of hot air is the systems fail-safe mode to keep people from freezing. I heard of some people getting these units repaired but most likely you will need to replace the unit. ($500)

I do hope it never acts up again...Good Luck

[Airbus]

My HVAC(heating ventl. & A/C) has been doing the same thing for 6 weeks now. I believe that the problem has to be the
"Control Unit" Part # 64 11 8 379 521, and the cheapest new unit you will find is at "Bavarian Autosport" www.bavauto.com for $275. But you have to install it, which I am certain is not a hard task. Should take about a 2 hours.
My local dealer (Scottsdale) will sell me the unit for $295, self install. But will charge me $430 for the part & install. This is the BMW Car Club member price. Also, I have found a used one at the junkyard for $150, but I don't feel that's a kosher way to go. And last but not least, I have a friend who is quite high at BMW in Munich Germany, he is researching this problem because I have let him know that this "Control unit" failure happens very very often. I have read about it at numerous web sites.

Steve

[shuasha]

They're charging you $135 for a 5 minute install that doesn't even require a tool?!!?!?!? All you have to do is put your finger through the top of the sunglass holder, push up the retaining clip on the bottom of the AC control unit, and push it out! Swap the unit, then just push it back into place. Hell, it shouldn't even take 5 minutes.

I've been having the same problem, but I think i'm going to try to repair the old unit before buying a new one. What is there to lose, really?

[jonesygrl]

There's probably a real *technical* way to install it...and they can charge that much for the "fake" time

Airbus: is the "control unit" you're talking about the whole digital read-out piece? Or is it something attached to that? Personally, knowing how often people have this problem, I wouldn't want to buy a used one- you never know!

I don't think this problem is specific to E36's either: I have a friend who I think just replaced his '95 7-series "control unit".

Of course, my car hasn't done this again....Ghosts in my car, I swear

[wdmurphy]

Update on getting the part at a better price.
www.pacificbmw.com
1-800-909-7278 this is their wholesale number. They will sell to anyone at wholesale rates as long as you are not in CA (I believe).

I just bought a new one for $238.08 USD including shipping.

[Vasilios]

My mechanic got me one for 130 i think.... and YES the installation is easy its about 4 minutes dont let them rip you off.

[gigel]

OK, my unit started doing this. But I plan on fixing it. For now, I just take the OBC out (it's not all the way in) and touch the wires when it's happening, and that cures the problem. I took the unit out, take it apart, look at it and looks good. I plugged it in, and no matter how hard I tried, I could not make it act bad. So, I could use anybody's help, if you can describe the symptoms. Mine seems to be doing this when it's hot in the car (car sits for a while), after the AC cools it down it's OK. Also, it doesn't do it in the mornings.
I have the 2 simptoms described here: unit OFF completelly, and display faded, with buttons being inoperative.
Anybody can describe their problems?

[shuasha]

I have exactly the same symptoms that you do. Temperature has a big effect on whether it works or not. I took mine apart a few weeks ago and resoldered a few places, but it made no difference. I'm going to completely remove a couple of parts this weekend as described in my earlier thread here. I'll let you guys know how it goes.

[gigel]

I will try the capacitor solution, as some other people say in the post. Usually when temperature is a factor, capacitors are involved
Thanks for the link, the search didn't return it...

[gigel]

OK, I replaced the capacitor. I will see if this solves the problem.

[shuasha]

Please let me know!! I want to Radio Shack today, and they had 47, 4.7, and 0.047 uF caps, but no .47. I didn't get to open the module today, so I'll see later if the data in the previous post was off by a decimal place.

[ 04-17-2003: Message edited by: shuasha ]

[CPAScott]

According to my local BMW dealership there are actually TWO parts that this could be -- a 2-plug one and a 3-plug one. The part numbers are 64 11 8 379 521 and 64 11 8 378 466, although I'm not sure which part number refers to which part.

Pacific BMW's price is absolutely correct, but there are NO returns. So, to be 100% sure, I need to take this unit out. Anyone who's done it, can they walk through step by step? I have a 1996 318i convertible if that makes a difference.

Many thanks!

[jonesygrl]

Cristian...did changing the capacitor work?

Mine has started doing it a lot- and there's no rhyme or reason to it's shutting itelf off. Right now I don't mind, but this summer it will suck if the AC won't come on!

Let us know what part no. you figure out, CPAScott!

[gigel]

Shuasha, the capacitor is 0.47 micro. Mine was 63V, but that's irelevant, as long as the voltage is > 35 V.