This has me beat. Occasionally my Octavia car alarm sounds for about 5 - 10 seconds and switches off again. It's only ever happened after dark (to my knowledge) and when it's finished the car is still locked, with no lights flashing or anything.

Any ideas as to what causes it?

 

I'm making the assumption that it IS my car alarm, as it seems to come from our car port, but I've never been quick enough to see anything, although a month or so back a neighbour saw my car hazard light flashing but the alarm wasn't sounding.

might be a flying insect inside the car, fly, moth, daddy longlegs etc. had a similar thing happen to me during the day when I nipped into a shop. turned out to be a moth which chose to fly round the inside of the car after I'd left.

might be a flying insect inside the car, fly, moth, daddy longlegs etc. had a similar thing happen to me during the day when I nipped into a shop. turned out to be a moth which chose to fly round the inside of the car after I'd left.

Thanks, I'll check it out. I just can't figure out why it stops so quickly.

Likely a fly or spider.

Someone with vcds can tell you the reason it went off

Mine went off for the 1st time ever on Friday night, seems I in-advertently locked the Mrs in side it whilst popping into the chippy. My mobile was also on silent so didn't hear the 3 times she called whilst locked in the car with the alarm blarring, my ears rang for quite sometime after I eventually got back to the car...

Ha this made me smile! make her go and get the chips next time....

Likely a fly or spider.

Someone with vcds can tell you the reason it went off

I didn't know vcds could tell the difference between spiders and flies. can it tell it was a wasp or a moth as well....

My bike would set off car alarms outside work, but not at home.  Perhaps they had got used to it.

Mine went off for the 1st time ever on Friday night, seems I in-advertently locked the Mrs in side it whilst popping into the chippy. My mobile was also on silent so didn't hear the 3 times she called whilst locked in the car with the alarm blarring, my ears rang for quite sometime after I eventually got back to the car...

When I first got together with the wife I had a clio with a Clifford alarm which automatically locked after a period of time and armed the alarm.

Came back from the tesco kiosk to a most unhappy lady. Surprised we made it past week 2.

The thing you need answering is why it only goes off for 5-10 seconds and not the full 30 seconds. If it was something triggering it them it would sound for the full cycle bit as yours doesn't it points to a fault somewhere.

A scan may reveal all but the siren would be my first guess.

Yeah, something is a miss here, 5-10 seconds is too short.

 

Having the hazard lights flashing without the alarm sounding is also a concern.

 

A sure fire recipie for a flat battery too.

I had a similar issue with a previous car- a 2001 A4. It would go off at random times at night and began to really **** the neighbours off. Turns out the back- up battery built into the alarm was on the way out and that's just what it did. I couldn't afford to replace it at the time, so my local indy just disconnected the siren. Job done

I had this happen to my FL vRS in Poland.....found that there were a dozen flies flying about when there was sunlight and disrupting the sensors.....either way not happened since....