Broken AC button fixed - here is how

How to (if you are lucky) fix the problem with an AC on/off button not springing back.

This description apply to a Skoda Octavia 1.8T -00 with a standard AC, i.e not "climate control" (I believe it's called ACC).

This problem appeared after yours truly "accidentally" removed the AC on/off and recirculate on/off buttons. When plugging them back, only the re-circulate button worked whereas the AC button lost its "spring back" action.

A short description about the problem in detail; The two buttons (AC and re-circulate) works in the same fashion as a ballpen, when you push it the linear action is transformed into a revolving action and alternates between getting stuck in the "in" position and the "out" position. Does that description make any sense ?

There are two separate switches built from tiny plastic parts, a spring and a contactor made from copper. Unfortunately everything is custom made and you cannot replace it with a standard micro switch.

The chance you have to rescue the situation is to switch places of the two identical switches, if you are lucky and the right part broke as a result of removing the buttons.

If you have the buttons removed, you can peek into the holes from the front and detect a few very tiny black plastic tabs sticking down from the top of the holes. When everything is as it should be you should have 4 of them. There is 2 of them in each switch mechanism, most certainly you are missing one of them in the AC-button hole.

The fortunate thing is that the AC-button uses one of them (can't remember if it is right or left tab) and the re-circulate button uses the other...

...yes, you've figured it out, thats why switching places may help.

If you've broken two "right tabs" or two "left tabs" you have to buy a new control unit. Sorry.

If you now are lucky and you have the buttons already removed you can proceed according to the very short description below (I think you can work out most of it yourself if you have gotten this far), make sure to take care of the tiny springs that makes them spring back.

If your AC/re-circulate buttons at this point _not_ are removed I urge you to _not_ remove them without first removing the complete unit from the car so that you can do this in a controlled way on a work bench. It is a _very_ delicate manouver to remove the buttons without further destroying the tabs. If you are in this position you will need to remove the glove compartment and what not to remove the control cluster from the backside of the panel (so to speak).

If you _do_ have the buttons out already it is perfectly possible to remove, repair and put back the unit without removing the glove compartment and panels around it. Not easy, but possible - small hands will certainly help.

OK, here's how:

1) Remove all knobs on the control cluster; hot/cold, fan and where the air comes from. To remove the fan knob I think it must be in position "2", the other could just be pulled straight out in whatever position (NB. Do NOT remove AC/re-circulate buttons with unit in car if you want to be safe)

2) Remove light bulb (in center of fan knob position) and the black piece of plastic with the symbols, it is "snapped" into place on the white main unit

3) Remove 4 screws (torx) holding the white plastic main unit

4) Push the white plastic main unit (WPMU) into the hole, twist, turn and wiggle it and with the help of a screwdriver open the locks for the red plastic parts holding the ends of the wire sleeves (the wires is what actually controls the airflow lids/motors). Remove all three sleeves and use a plier to grab the wires to get the loops off the attachment points (you'll understand once you've looked inside)

5) Detach the fan-motor and AC-control electrical connectors

6) Wiggle out the WPMU

(4,5 and 6 may be easier if you also remove the ashtray assembly since you then can reach in behind the unit from underneath)

7) Go to your work bench whilst staring with an evil eye on your WPMU

8) On the underside of the WMPU there is a small white tilting "bridge" that prevents the re-circulate button to be engaged when you are using full defrost on the windshield. It's a small spring loaded device - remove it

9) Look carefully in the center where you have the fan speed control unit, that whole assembly is snapped into place into the WPMU. Wiggle a little around the three plastic tabs holding it and remove it

10) Remove what looks lika printed board assembly, but what really is a bunch of solid copper leads baked into some black plastic

11) Now the switch mechanism shold be completely exposed and you should be able to figure out whether you can repair it or not. Most likely it is enough with removing any debris that may gotten stuck, swap places and then put everything together again

(And yes, it is completely unacceptable that Skoda/Audi/VW doesn't sell these small ****ty plastic parts separately - in this case a broken 1 cent plastic piece will cost you a complete replacement of the control unit which costs EUR430 (yes-fourhundredandthirty!!!) at my local Skoda dealer)

12) Assemble in reverse order. In the case of assembly it is necessary to remove the ashtray assembly to gain access from underneath to be able to mount one of the wire sleeve mountings (the red piece of plastic that goes into the white and then snaps into place)

Do NOT under any circumstances dry fit your AC/re-circulate buttons after you have mounted your fan-speed control unit assembly into the WMCU, not before you have everything in place. This should be your absolute last thing. And then two things are important.

12.1) Remember the tiny springs

12.2) Mount both of them simultaneously !! If you accidentally mount the AC-button first you can't get the re-circulate button in, which means you have to remove the AC-button again and what will happen then ? Yes, you are basically forced to remove everything again, this time the tedious way since you want to remove it with the buttons still in place

If anyone knows another way to fix this I'm all ears. This is how I did it.

Good luck !

/Anders Pettersson