Alarm goes off in petrol stations !!

[Justin182]

Whats the deal with this !!

Ive fitted a fancy Cobra alarm included level/tilt sensors etc.... the works, about a year ago and it has worked flawlessly, except for this same problem time and time again.

When i fill up, i sometimes lock the car when paying depending on surroundings etc... and i would say 30% of the time the alarm goes off when im paying if i lock the car. It has done this many times now and has never ever happened anywhere else... always when im paying. Its like its saying " cheers mate for the V-power... yum yum !!" lol

Everyone in the station cr&pped themselves when it went off... and im standing there like a muppet with my key against the window. lol

Anyone the faintest idea what causes this ?

Im baffled.

 

[BrianR]

Did you ever consider the possibility that adding fuel might just change the weight of the car at the rear and set the level reference monitor off ???

 

[Justin182]

I havnt actually but it would go off straight away, and not when paying. It does go off straight away if i forget and start jacking it up... just one of those things, eh.

 

[rory182]

maybe ur opening the door too quickly unlock on the approach and give it maybe 5 seconds and it doesnt go off.

Only happens to me when passengers are waiting for me to unlock and they grab the handle as soon as its unlocked and set it off.

 

[kneebs76]

I havnt actually but it would go off straight away, and not when paying. It does go off straight away if i forget and start jacking it up... just one of those things, eh.

Does it not take a few seconds to fully activate ? But then again I suppose if it did, the weight of the fuel would've caused the backend to drop by then anyway/////

 

[BrianR]

One way to check that its not something peculiar to the filling station is to try it at home by placing a heavy item in the boot and locking the car.

 

[bacon.egg]

The cobra alarms give a readback on the led after they have sounded and youve disarmed it. Look it up in the manual and it'l tell you which sensor it relates to.

If i had a guess though i'd say its the ultrasonics inside as they sometimes see heat rising out of the vents and set off. I had to sort this on my own 172 as it kept false alarming.

By the way the reason it doesnt go off straight away is because it takes 45 seconds for the system to arm.

Hope this helps you.

 

[bmh.01]

I havnt actually but it would go off straight away, and not when paying. It does go off straight away if i forget and start jacking it up... just one of those things, eh.

Does it not take a few seconds to fully activate ? But then again I suppose if it did, the weight of the fuel would've caused the backend to drop by then anyway/////

Yeh they take 40 seconds from you locking the car and it arming before it goes active and can be triggered. The level reference could be whats setting it off, if the LED shows an external trip then i'd say thats what it is.

 

[mini-valver]

Put a 10er in a time and make 4 trips? lol

 

[Justin182]

Ive looked up the flashing codes and seems it was the ultrasonics that were triggered...... although that makes it even more confusing lol

I was thinking that maybe its the fumes of petrol coming through the vents, and the ultrasonics are just very sensitive.

Still very strange that in over a year, the alarm has never gone off anywhere except petrol stations, and is consistant.

 

[172.com]

Do you arm it before you fill up or after? If it's the fuel doing it, only arm after you've finished filling up.

I used to have an after market alarm (I forget which) on my old clio, that fucker would go off (very loudly) if you left the hazards on! Used to annoy me when parking up on double yellows, whilst causing a traffic jam with my inappropiate parking, with my harzards on to warn other motorists of the impending danger of my car being parked up.