Aircon button not staying depressed!

  • Hello,


    The aircon button on my head unit is not staying depressed when pressed in. Had some OBC work done previously by M8-Enzo, so contacted him; he said it was an easy fix, but I have been unable to contact him since, hope he's ok. As he said it was an easy fix, I thought I'd look at the unit myself. Have taken it apart, but now have got to a point and don't know how to continue! See attached photo, the plastic and metal cradle that the buttons sit in does not have any obvious signs of being able to be dismantled, any ideas, anyone done this, anyone know if I indeed have reached the end of what can be dismantled, is this a sealed unit???


    8er.org/forum/index.php?attachment/39659/


    Also, if I put a RHD unit in a LHD car, will it function correctly? I ask because I have noticed that on my unit, the center and driver-side wheels have little buttons so that the wheels click into the extreme rotations (see buttons on photo below), but not so with the passenger side wheel!? Not sure if this will affect RHD v LHD?


    8er.org/forum/index.php?attachment/39660/




    Thank You,


    Ivan

  • The detents on the drivers-side temperature setting can over-ride the passenger side temperature setting - so there should be no problem using the wrong country variant except your passenger can boil or freeze you! I've never had those switches apart so can't help with them....

  • I think you should keep trying to reach Guido (M8-Enzo) and get some help from him.
    I found one old thread over at Bimmerforums in which Revtor wrote about changing the illumination on the HVAC unit.
    There are some images of the disassembled HVAC controller but he did not removed the microswitches so it's not much help.
    (Here are the Links: Link1, Link2)

  • Cheers Timm, good to see you're still on here. I've bought the UK unit after all...


    Steve, I initially contacted Guido in February, he got back to me mid March, and then went 'quiet'. Emailed him a further 4 times over the next couple of months, but to no avail!? The links you sent, I checked, but like you say nothing about dismantling the microswitch cradles. Maybe can't be done? Had a good look at it and other than using force (!) couldn't see how it possible comes apart.

    01/1994 E31 840i M60 European LHD automatic, prod code EF61

  • Looking at the images, you would need to desolder the LEDs and probably the metal cradle is also soldered on.
    If you have an Ohm Meter you could try to put one end on to the cradle and then look for corresponding solder points on the other side.
    It certainly looks like a lot of soldering (you would need a desloder pump as well) and I'm not quite sure, that it is possible to solder everything back as tidy as original.


    Strange thing with Guido. I had a mail conversation with him in June and sent him my BC to repair the Pixels early July. He sent it back within two days perfectly repaired.
    Did you try to call him?

  • Hi Steve,


    Thanks for response. Been away on holiday last couple of weeks. What you suggest is way above my skill level I'm afraid. Have bought another unit anyway. Yes, very strange about Guido, and no, didn't call him as it seemed a bit impertinent.


    Ivan...

    01/1994 E31 840i M60 European LHD automatic, prod code EF61

  • Update... Guido says he can fix the aircon unit but needs a donor unit to transfer the air-con button cluster over, so if anyone knows of an old bust up unit that has the aircon button still working, please let me know...


    Much appreciated,


    Ivan

    01/1994 E31 840i M60 European LHD automatic, prod code EF61

  • Hello,


    While exhaustively searching for an aircon unit for my car, I came across a 5 series E34 unit (see picture) which looks like the button clusters might be the same as our 8's (remember, just looking for donor air-con button-cluster for my unit). Does anyone know if these button clusters are the same fit as our 8's?


    8er.org/forum/index.php?attachment/39872/


    Cheers,


    Ivan

  • IvanT: The E32/E34 HVAC/IHKA control unit has quite a different internal construction despite the very similar looks. You will not find suitable donor parts in it. This eBay auction has a few pictures that clearly show the different button mechanisms.


    If you are brave you could try to disassemble the buttons. These old style buttons often share the same switch mechanism for momentary and latching switches with an external spring/latch being the difference. Maybe that broke or came dislodged. Sadly I can't say for sure this is the case with the HVAC control unit buttons. It's been many years since I had my HVAC control unit open. I don't remember all details but I do recall that I could not get access to the individual switches due to the metal brace over them. I forgot how that brace is attached but I think the only way to get access to the individual switches was to desolder them from the PCB (which I did not attempt). If you'd like to give this a try you'll need a proper desoldering iron/gun. Solder wick or a solder sucker won't do the job. There's a lot of pins to desolder and these old PCBs are easily damaged (traces and pads lifting) from excessive and prolonged heat. Even if the switches do not have an external latching mechanism (or it cannot be repaired), you might be able to locate the manufacturer and part number. Maybe replacements can be found. Anyway, there are a lot of uncertainties here. There may not be an external latch, it may not be repairable, and the switches may no longer be available with no suitable replacements.


    If you decide to replace the RHD control unit with a LHD version, the passenger-side roller wheel indeed becomes the master (overriding the driver-side roller wheel when set to the maximum/minimum)? If that is annoying/undesired you can simply desolder the passenger side microswitch and move it to the other side. If you look at the PCB you'll notice that the solder islands and switch outline are present next to the other roller wheel.

  • Hello Revtor,


    Thank you for the advice. Unfortunately, the UK unit was lost in transit! The Seller, BigSteve, did however insure the parcel and has therefore refunded me. I have sourced another unit here in Spain with working buttons and am awaiting delivery. The Gods will surely not let this one get lost! The repair that you mention I believe is a bit beyond me, and Guido of M8-Enzo advised me that donor button-pods are necessary as they cannot be fixed. I don't think I'd have attempted the fix anyway in case I damaged the unit further. I do not think I'll even put the LED bulbs in the replacement unit in case it was the fitting of that in the last unit that broke the button; I found the buttons when disassembling very hard to get off, and maybe broke something putting them back on. It's a pity because it was nice to have the dials properly illuminated.


    Regards,


    Ivan

    01/1994 E31 840i M60 European LHD automatic, prod code EF61

  • Hello All,


    My replacement aircon head-unit has now turned up, have cleaned it up and now ready to finally put my center-console back together. When I took it out, I was expecting a quick fix, and then straight back in, so I didn't label the plugs! Have now forgotten what was what!!!


    The following plug I believe is not relevant to my console, but it seems very familiar, but cannot find anywhere for it to plug into?
    8er.org/forum/index.php?attachment/39920/


    The following plug appears to be just a light plug...


    8er.org/forum/index.php?attachment/39921/


    ... and I assume plugs into the gear cluster to light up the gear shifter mechanism below?


    8er.org/forum/index.php?attachment/39919/


    However, that then leaves no plug to plug into the rear of the air-con panel (small plug above main one)!?!?!?


    8er.org/forum/index.php?attachment/39918/


    Can anyone advise?


    Regards,


    Ivan

  • The black 3-pin connector with grey/red and brown wires is X1193 and is indeed the light plug for the transmission position indicator.


    The 3-pin connector at the back of the HVAC control unit is X682 and is only used when the car is equipped with park ventilation and/or heating.


    The 6-pin does not ring a bell. Can you get me the exact pin layout and wire colors?

  • The 6 pin black may be X1599 for the "selector lever position switch" e.g. gearshift console.


    I always believed that the 3 pin at the back of the HVAC was for AUC, learn something new every day :D


    You´ll get there and maybe also find the cruise control plug Angus was looking for... ;)


    Cheers
    Reinhard

  • Thanks all,


    Put the three pin into the gear shift light socket as knew I needed that. The six pin, I just left, but all seems to working fine. Took the car for it's yearly, failed on emmissions, but that's a new post...


    Cheers,


    Ivan

    01/1994 E31 840i M60 European LHD automatic, prod code EF61

Jetzt mitmachen!

Sie haben noch kein Benutzerkonto auf unserer Seite? Registrieren Sie sich kostenlos und nehmen Sie an unserer Community teil!