Suko

I have a 2001 Allroad that has been excellent, but now have a vexing issue of just plain random activation of the the alarm. Does anyone have any ideas about this, best fixes, best trouble shooting.

Thanks for any ideas or if anyone has run into this before.

G0to60

Do you have any of your windows cracked or sunroof popped open? It could be the motion sensors are picking up the pressure difference caused by an open window. If nothing is open and it still goes off try turning off the motion sensors by pushing the button in the DS door jam next to the trunk button. If that fixes it then you can dig deeper into the motion sensors. If that doesn't work then it might be a door sensor is malfunctioning.

Mike B

This a common condition with the interior motion sensors on early Audi's which have this annoyance. Both my wife's '01 TT roadster and her '02 allroad have this problem.
In both cars we switch off the thing before leaving the car every time; part of the routine of exiting the vehicle.
The other cause may be something in your pocket with the key is pressing the panic button. This is also a feature of the early switch-blade keys. I carry 3 Audi keys (not the TT) and a small Swiss Army knife in my front right pocket and every so often when I bend over to pick something up, something presses against the key to the '02 allroad and sets it off. It never happens with the '03 allroad (or the '06 S4), so maybe they eliminated that annoyance from the standard equipment list beginning in '03.
There's a way to set the sensitivity of the motion sensor via the VAG Tool, so I've been told, but I gave up looking for it on the TT many years ago.
If you find out how to shut it off, let me know.

Stealth Beige

Check your key fob as well. I had a similar issue in a Nissan years ago, the alarm would randomly go on and off (once while driving-that was truly weird). In the end we found my 9 month old son had been chewing on the remote fob thing and either toothed or saliva'd a short circuit in there. We junked the fob and it never happened again.

Hopefully you're smarter than us and haven't let anyone lick your keychain, but keep it in mind anyway.

Suko

Hi All,

Great suggestions, thanks, I am new to the forum and the shared ideas are excellent. Here is what I know:
- the window rolled down has always tripped the alarm a problem so don't do that
- turning off the motion sensors also does not work
- my mechanic is definitely scratching his head on this as well, but he did disconnect the motion sensor switch from the entire circuit which worked for a about 2 weeks (is seems... this is so random that it is of course hard to track down with any certainty, although it seems to go off at about 12-14 minutes after locking the car)

I like the suggestion about a key fob gone bad, or, even a door sensor randomly misbehaving, I will look into that, but I believe that would show a signal coming to the onboard computer.

Thanks all, and if someone knows a way to simply shut off the alarm altogether....

A4 n00b

Another thing to consider is one of the latch sensors. Are you seeing any door or tailgate open warning on the dash? I know from experience that the hatch sensor going bad can cause the alarm to go off intermittently. Maybe throw that into the list of possibilities too.

AR4x4

I had this problem for ages - tried isolating motion sensors and other solutions - in the end, just turned off alarm system for the car.

Suko

Do you know the best way to turn off the car alarm entirely?

It seems my mechanic was not aware of how to do that. It may be the best option since I have tried everything possible, except the door latch on the front passenger side is "sticky" but it is a $400 repair so kind of waiting on that, and no open door sensors are being activated.

Would be fantastic to just take the car alarm completely off line!

AR4x4

My mechanic did these with VAG-com I believe. Sorry not much help :-(

Suko

Hi All,

Thanks for your input, it seems in the end I finally have it fixed. It was two parts, a) The right front passenger door latch assembly was worn out so it occassionally sent a bad signal that the door was open or closed b) the motion sensor was actually bad for a long time which is why the door could never be locked and a window cracked on hot days, for example. Took the sensor totally off line and all seems to be good now.

Thanks,

Gary