Heizung/Klima: Unknown type watervalve

[Markus525iT]

Werde ich bei Zeiten mal machen. Wäre schade, wenn jemand sich sonst nen Wolf sucht und nicht drauf kommt.

Markus

[Beumers]

I think I read almost all those articles but it's hard to get a clear image of the way the whole system works. It depends on what article you read first.
I watched all the youtube video's. But my type of valves isn't in there. It's not difficult to disassemble them though. There are just 2 rubber parts. I wonder why they are so expensive.

If the control panel in the car is the problem I can replace the panel with a spare one. I own one that should be problem free. I was planning to put it in the car as soon as I can get it out of the storage. My front window vents are blowing hot air what ever switch I press. Only resently I found out the passenger side is also not working as it should but at least I can switch it of. Driverside is oké.
If I can use the car again I have to figure out what exactly works and what doesn't.

It would be very helpfull if there was a flowchard to identify a problem in the heating/airco system step by step without having the possibility to forget something because you didn't know yet. This IHKA system seems worth the efford because it's quite complicated. Maybe if i'm done with it I know enought to try and make one.

Thanks for now. Regards Henk.

[Erich]

Klimaautomatik IHKA (German language PDF)
Seminar Arbeitsmaterial, 53 pages, it is all in here
 http://www.e38.org/e32/klimaautomatik.pdf

[Beumers]

Hi Erich.
Got the pdf already. read the whole article. It's alot to take in. Maybe I'm not able to crack the nut. For now I couldn't make a clear picture of it and have a full understanding how all the components affect each other.
But I'll keep trying.
Henk.

[Beumers]

Hallo Erich und Marcus.
Yesterday I was able to check for 12 v at pin 1 of the watervalve connector in the car.
Ignitionkey al the way to the right. Control unit on the dashboard switch on auto. No 12 volts.
If I read the electrical manual the right way the 12volt connection goes right trough fuse 33 to the control unit on the dash where it goes via switch auto directly to pin 1 for both the valves. The negative contact goes trough the control unit behind the sword to each valve separately.
It's the same way it is described in the pdf "klimaautomatik". I checked the electrical manual to be sure. (It would be very helpfull if everybody used the same description for the parts and units.)
For now I can rule out das Steuergerät I think. So first I have to find out why there is no 12volts on pin 1. Thanks for pointing that out again Marcus.
Now I have to wait untill I can go back to the car in the storage.
Keep you posted if I can.
Regards Henk.

[Beumers]

Looking trough the electrical sharts it seems simpel to find the connections from Fuse 33 to connector x35 (under dash) to x693 (control unit) back via x35 to x85 (pin 1) on the valves. There is one connection x853 that is a spice in the harnas somewhere in the right footwell. This connection is drawn like a dot. So it's not a clean runtrough but it must be a connection like a solder joint or something else. I cant find how this is doen.
Does anyone knows how slices are joint together? I never looked inside the harnas and I like to keep it that way. If it's not broke don't fix it.
Thanks.

[Markus525iT]

Hi, the issues is mostly in the control unit (head unit, where you can adjust temperature, fan speed and so on).
In german we call it Bedienteil.

If you switch the driver side temperature to warm, you will get a "click" noise at the end of the scala.
This click noise activates a switch which will take the 12 V of the wiring. It is meant to be an "emergency" function. If nothing works anymore, you can still get a heated car - just by switching of the 12V and getting a permanent open valve (without power the valve is always open)

Unfortunatelly that switch often gets broken and does not release anymore. Result is that you do never get power again.


You can measure if the switch has pass or not.

Another issues could be a rotten cable direct at the heating valve.

Markus

[Beumers]

Oké. So if I understand correctly it's not a separate switch at the end of the scale at the drivers side. So if the switch itself is broken it also diconnects the path to the auto setting. Now you point that out it makes sense in the drawing of the part.
But than why is the driverside working like it should but the passinger side is not. Uncontrolable are the airvents to the front window. Defrost position as it seems. I had them blocked with tape in summer. There was no way I could switch it of. Does it make any sense to you?

I just looked at the valves. They are worn but not fallen apart so they have to work. Maybe leeking a little bit but that should not be the reason the temperature is extremely high.

Henk.

[Erich]

when the driver side temperature switch is set to full heat and you hear the click, that means - as Markus already pointed out - that the switch will take the 12 V off the wiring and the temperature is no longer controllable = always full heat, and it overrides also the passenger setting.
You can disassemble the switch and test it, or use a known working Bedienteil.
Here are all the single parts disassembled  http://web.archive.org/web/200206091...w.com/ac_cont/

[Beumers]

Hi Erich.
I knew the switch desconnected the 12 volts. But didn't know the same switch was also connected to the auto circuit. So if the switch is faulty the auto circuit is desconnected to. I think it's not a logic thing to do but so be it.
I took my unit apart years ago. I din't check the switch at that time but I hear the click when I turn the wheel into the last position. I put in a spare unit for that reason that should be oké. I hear the click here also but I'll check it anyway.
What I was trying to point out is that if the driverside is oké than the switch cannot be faulty because the driverside would not work properly but it does. The passenger side does not and the frontwindow vents are by no means controlable. They blow hot ait no matter what. This is not the behavour of a faulty switch if I understood everything correctly.
Henk.