Possible causes for alarm going off randomly

[outasight]

Hi folks,

As it says, I'm looking for other's ideas on possible causes for the "alarm"(car horn & hazards)going off twice lately - totally at random. No windows down, no wind to speak of, no spiders inside known(can't say for certain about a fly though).

My theory is that the car was parked on sloping ground one time, and uneven ground the other. Both were a similar amount of time, perhaps 5-10 minutes, after deadlocking(the normal habit way of locking). I reckon it may be caused by the height suddenly dropping, as we have noted they can do without warning after some time stopped(running or not!).

Have others experienced this too?

Regards,

Les.

[WhiteD3]

Check the bonnet sensor as this was the culprit in my d3.

Having said that.........I work with two blokes with d3's and it is a common occurrence when they're all parked out front for one to go off followed seconds later by the other two, no rhyme or reason to it. Hit the remote on the offending d3 and they all stop. Go figure.

[discotwinturbo]

My D4 alarm went off with me standing at the front of it at the pub. I put my beer on the bull bar. I fiddled with the grill (sometimes my hands wander) and the alarm went off.

Brett

[Josh_WA]

My d3 used to do this for the last 6 months I had it. . Checked the sensors and the only suggested fix from the dealers and workshops was to change out the Security ECU (BCM I think they called it) to remove the faults causing it.

I traded it in so it's somebody else's problem now :)

Cheers

[Ozzy119]

Hi,

My D4 has done this twice that I know of as it was on my driveway and I was home. (I have no idea if it has happened while at work or out and about)

On both known times it happened about 5-10 mins after locking it, but not the dead lock, just one press. My driveway has a gentle downward slope, car facing up hill.

[Tinman]

Had the same problem with my D3. Turned out to be the bonnet close switch. There is a micro switch on the lhs latch looking from the front. I unpluged it and bridged the cable taped it up no more problem. You could replace it if you wanted to.

[Fatso]

Not sure if applicabl but the swmbo,s falcon started sounding the alarm after parking up , turned out that there was moisture in the key remote actuating the panic alarm .

[outasight]

Hi,

My D4 has done this twice that I know of as it was on my driveway and I was home. (I have no idea if it has happened while at work or out and about)

On both known times it happened about 5-10 mins after locking it, but not the dead lock, just one press. My driveway has a gentle downward slope, car facing up hill.

Hey Ozzy,

In your case it is not armed for interior movement then, only perimeter(doors etc.), so your's may be easier to trace than mine so far...

Thanks too to everyone else's feedback - sounds quite common then!

Regards,

Les.

[WhiteD3]

My personal theory is interference. Both the D3 which I had for 4 years and the D4 which I've had for 1 year will go off at work, never at home. The only diff I can see is that at home its in the garage, at work its out in the sun.

As I've said above, when it goes off at work the 2 other D3's will also go off. Not at the same instance but within a few seconds of each other. Disarm one and they all stop.

I think it could be a false alarm in one that sets off the others.

[outasight]

Yeah, not sure all causes are the same, the interior would be ultrasonics, so sound waves of any sort could cause it.

I was just re-reading the manual on the reverse sensor thing, so looked at the alarm part as well & noted the full alarm will trigger on any tilt etc. too.

I reckon that's why it's gone off in my drive(slope) & at the pub in Buchan(uneven slope into gutter). Both times I had not lowered the D4 into access mode which I tend to do by habit most times I leave the car parked. The sudden drop in one corner I've felt before when stopped could be a perfect cause in those cases too.

Regards,

Les.

[dominicbeirne]

when it goes off at work the 2 other D3's will also go off. Not at the same instance but within a few seconds of each other. Disarm one and they all stop.

I think it could be a false alarm in one that sets off the others.

Just being watchdogs I reckon, or a good looking lady D3 went past, :D but seriously I have had similar issue and bonnet sensor was replaced. Have also had constant niggles around the central locking with fuel flap not locking etc

[Scouse]

Hi folks,

As it says, I'm looking for other's ideas on possible causes for the "alarm"(car horn & hazards)going off twice lately - totally at random. No windows down, no wind to speak of, no spiders inside known(can't say for certain about a fly though).

My theory is that the car was parked on sloping ground one time, and uneven ground the other. Both were a similar amount of time, perhaps 5-10 minutes, after deadlocking(the normal habit way of locking). I reckon it may be caused by the height suddenly dropping, as we have noted they can do without warning after some time stopped(running or not!).

Have others experienced this too?

Regards,

Les.A dealer can check the alarm trigger history. Chances are it will be the bonnet switch as previously mentioned.