GT6ixer

I never had an issue with my car's alarm. Still don't, really. Every once in a while it gets armed (not sure what I am doing to arm it honestly) and when I open an unlocked door without the key it goes off. No big deal. I put the key in and turn it and it goes off.

However recently I have noticed this scenario. I get out of the car and don't lock the door. I can open the door right away or a few minutes later and the alarm does not go off. However if I wait, for example overnight, and then open the door the alarm will go off. So does the alarm have a function such that if it knows a door is unlocked it will arm the alarm after an specified amount of time? I checked the OM and it doesn't mention anything related to that.

Bertrand Daoust

I can leave the car unlocked in the garage, for days/weeks. Never experienced this.
Possibly something wrong in the alarm module. Just saying...

928NOOBIE

The alarm can be set to arm passively, which it sounds like could be happening.

As I remember, the info to change it from passive to active arming (on my car, you have to lock the drivers' door with the master key to arm) is a mixmash of back and forth with the master key in the driver's door lock within a number of seconds.

This is a maddeningly random piece of information that for some reason I also have not been able to find again...this happened to me and I honestly lucked into resetting it back to active arming. I'll poke around and see if I can locate the info again....it was in a wierd place..not where the usual suspects put stuff...

928NOOBIE

Didn't read all of this...but maybe might help?

https://www.porscherepair.us/alarm-s...rm-system.html

GT6ixer

Interesting and thanks. This is applicable to a '91 model, so I'm not sure mine operates the same way. But regardless, I think I figured out what is going on. I went out at lunch today and played around with it. So to begin, my central locking system is apparently not working correctly, as in if both doors are unlocked and I use the key to lock one door, the opposite door stays unlocked. From what I have been told, both doors should lock when using the key. So what was happening is that I would lock the passenger side door but forget to go around and lock the driver's side. The alarm gets activated when locking either door, but because the other door is unlocked, when you open it the alarm gets triggered. It has nothing to do with time like I initially thought. It's just the fact that I can lock one door independently of the other. I'll have to look into getting them synced up.

Thanks for the info!

DR

Hi Nate,

Check the little glass fuses that are clipped on the back top of the Fuse/Relay Panel. (IIRC 500ma slow blow). One blown will give you that behavior.

Happy Tueday,

Dave

davek9

Good one to note Dave, Nate try using the Hatch lock to arm or disarm the alarm and see if that helps.

Dave K

Alan

The alarm is only ever supposed to arm using the key (as that article notes). If yours ever self-arms - that is a fault

Alan

hwyengr

Both doors should lock even without the key. If you work one lock from inside the car, the other side should do the same.

Alan

True - and if that doesn't work it is also a problem. However this is mostly unrelated to the question of how the alarm arms (arming should always need a key).

Seems in this case IT DID and was just masked by the other central locking failure...

Alan