Key in ignition horn doesn't work, key out of ignition horn works.
 

As the title says. Key in ignition, the horn doesn't work. Key out of ignition, the horn works. Is this an ignition switch issue? Thanks.

Sure sounds like ignition switch.

Any recommended brand to go with?

Also noticed the electric side mirror adjuster isn't working. Not sure if that has anything to do with the ignition switch.

I think Meyle is a good brand for the ignition switch. I know that the Chinese version that NAPA sells will only last about 6 months, it is made from a much more brittle plastic.

Key in ignition horn doesn't work, key out of ignition horn works.
 

Thanks Paul. Meyle seems to be a decent quality company. Can't believe the part is only $7.

Interesting tool kit to do this job
Headlamp
Stubby screwdriver(Search for details)
Ibuprofen because of the contortions required to access it :-)
Also some debate about how to improve access- via a removed vent?
Careful you don't dislodge other connectors when fighting for access.
Good luck with this tedious job.

Yeah, doesn't look like a fun job trying to get to it.

Watched a video on it. The guy pulled the vent pipe, said the screws turned out easily, of course not easy to get to, but he did the job in 25 min.

My car did the same thing with the horn, there is a ground on the steering wheel under the airbag that was broken, the sheathing was intact but the wire underneath was broken. Undo the battery, wait a while and remove the airbag. There is a female ground connector on the steering wheel, check if it is still intact. I reconnected the ground with a new connector. Works fine now.:cheers:

Looks like I'll be pulling the steering wheel. Thanks for the info. :cheers:

Did you have to pull the clock spring?

No need to pull the whole steering wheel off, just remove the two torx screws holding the airbag on the back side of the steering wheel, carefully lift the airbag off. It’s a little hard to hold the airbag and replace the connector at the same time, the airbag fell off and got unplugged when I was doing it. Luckily I followed the instructions on undoing the battery before doing this repair. Or else the reset by the dealer would be needed. It was much easier to fix the connector without having to hold the airbag. Took 5 minutes to replace the connector and replace the airbag.

That ground is behind the airbag (no need to pull the steering wheel). You should get a spare switch either way, especially if you've never replaced it.

If you need any help tracking it down, you can always swing by. ;)

Well that makes sense. Been a while since I put in the 4 stalk. The old brain is going bad, part number for a upgraded replacement? :D

I'll order in a switch also, have some other funny stuff going on that may be related. I read it can affect the air conditioning and this summer the air quit working. Today I was reading a thread where a guy said if he moved the ignition key the air would work. Also there are times when I turn on the lights, my rear spoiler wants to pull itself down and I can hear it grinding. When that happens, the voltage and oil idiots lights come on too. I have to shut the car off, turn off the lights and restart it to make it stop. Plus I have the electric adjustment for the side mirrors not working. Not sure if that is related to the switch in any way.

There are some photos of that specific issue IIRC. It is a Flag connector and a Brown wire.The wire breaks internally(insulation looks good) near the Flag connector.
My recollection is that to access this you need to remove the 2 'secret' screws behind the Steering wheel to remove the Airbag. Those screws are Torx. If they just rotate endlessly without loosening the Airbag - we both have the same problem ! I have no solution for removing the Airbag.Hopefully others will be able to suggest something.
There is a Youtube for the 'broken wire' job.

I finally got around to installing the ignition switch, holy cow I was lazy in 2018. Yes it was a PITA.

Anyways, replacing the switch does appear to have fixed the odd deal with my spoiler getting pulled down when I turn on the headlights and the voltage and oil idiots lights coming on.

It did not fix the air conditioning issue or the electric adjustment for the side mirrors not working.

Steelepuls was correct on the wire under the air bag being broke off. Not only did it make the horn not work, it also made the Tiptronic buttons on the steering wheel not work. Got the wire attached back and both are working fine.

The air conditioning is stumping me. When I turn on the air, I feel the engine RPM drop down a bit from the compressor kicking on. The fan is working fine, climate control unit displays everything correctly. I even tried a different climate control unit in the dash, still no cold air coming out. I have checked the system pressure and it's fine, even added a bit more R-134a to the system just to put it in the middle of the green area on the gauge. Heat works perfectly fine. What gives on the A/C not working?

Got the Durametric out and had it run a test on my A/C system. It was telling me before there was an issue in the climate control unit, that's why I tried a different unit. Now it's giving me this error. Not exactly sure what I need to fix to fix this issue? Not sure if that would fix the A/C not blowing cold air either. The heater works fine.

https://i.postimg.cc/PxNZXPv7/air.jpg

Just a note on removing the airbag if you do. The bolts are soft, be careful to not cross thread them when you reinstall the airbag. It’s easy to do.