When I still had my old golf (God rest his soul) gave me the idea, the infrared remote control of my car stereo installed in the steering wheel. The advantages are obvious: The fingers stay where they belong, at the knee of girlfriend .
The whole is really only for cars without airbags, if only because under the horn switch is enough room for the electronics. My new car, a VW Bora has an air bag and I'm going here to find another solution. However, not infrared, but a few contacts in the slip ring.

Well, back to the steering wheel without airbag. First, expand and withdraw before the horn cover. Careful not to bend the plate too much, otherwise the car honks sporadically in the most unlikely situations. I speak from experience because . If you then have the steering wheel in your hand, you put the right one for you first set the switch position and pick the electronics retailer you trust a few appropriate pushbutton. For me there are four important ones: Loud, quiet, front track, back track.
The steering wheel of golf (and perhaps other) is mainly made of PU foam inside and outside covered with Kunst-/Leder. We therefore draw on the position of the switch and then just cut the first thin top layer with a thin sharp knife or scalpel. Dear little tighter, then there are no ugly gaps. A template is not too bad, then the switch succeed on the other side as well.
The foam underneath is very soft and can be easily formed and press. Now you can stab with a screwdriver or something else long and pointed, a small channel for the cable to the switch in the large hollow space beneath the horn. The stability of the steering wheel does nothing, because deep down inside of the foam is still somewhere in a steel frame. The same switch can be provided with short connection cable and pass through the small channels in the middle. If you have it fitted nicely into the holes, they should still be fixed with a small drop of glue in her hole.
Now we need to ensure that the remote control can also act in the direction of the radio. In addition I have (seen from front) right rear housed the infrared diode that provide them with the knee of the driver may be inclined to send away to the radio. Must be extended to this diode are soldered with 2 cables, just like the switches on the board of the remote control. But beware! Diodes always look for in the right direction! The channel back to the drill with screwdriver towards the center, pull the cord and glue the LED in its hole.
Now that we have caused a lot of cables under the horn switch, we should add this also. That depends entirely on how the radio remote control of your looks. Which do have a bank card, and some in thicker design with 2 AAA batteries. I have used the latter, however, had to sacrifice the housing around it, because otherwise it would have been too narrow. The battery I have, however, re-used. Who still has limited space and can be brave, even a bit of the foam cut away to create more interior space.
Yes, now only have the cable in the right places to be soldered to the motherboard. Most remotes have it rubber-membrane key with a conductive carbon layer on the bottom. This simply pushes on two bare spots on the board and initiates the switching process. On these two points per key blank you can directly solder the wires. The diode must also re-soldered where you have just soldered them yet. The polarity!
The art is to make the cable long enough that you can screw behind the steering wheel and then stuff the electronics into the hole, and short enough to not block a giant ball of the horn. The whole thing then you can also check before installation to function, of course, with batteries.

This should also be Been. Would be happy if it has anything to you even went so well and you send me a photo of it, maybe I can add this here.

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