Hi guys - first post on this forum!

Having a weird problem with my Mongoose M20/M20S alarm, where the siren randomly goes off.

I've had the car for about 8wks (and alarm was already installed), and previous owner is not sure of the problem/cause.

It does it about 2-3 times a day, whether it be parked in the garage or outside somewhere.

I initially thought is was the shock sensor (it's mounted to the steering column), so turned it down (and also programmed it off)...but still no luck.

Then I thought the battery was getting weak (taking a bit more time to turn over), so replaced it as well...was all good for the past week, then it started doing it again!!

Any ideas on what it could be? The car is stock, ie no aftermarket stereo etc...apart from a previously installed earthing kit.

Anyone in Melbourne who would be recommended to have a look at it?

Cheers!

im not sure about the mongoose, but all alarms ive worked with will use a series of flashes of the LED to indicate which "entry" point has been triggered. sometimes u need to turn the igntion on for the flashes but it should tell you in the owners manual.

Does the siern have a keylock on the back to disable it? maybe its internal battery is going flat too?

Thx for the reply guys!
Um...i'll have to double check the indicator flash sequence, but I think it relates to a door/entry sensor.
The siren has a key-lock to turn down the volume, but I'm not sure how to tell (or change) if the back-up battery is flat?

Thanks again!

what type of car is it?
does it have a bonnet switch installed? could be faulty...

Check all door/boot/bonnet switchs, it is likely that one of them isn't connecting properly, and could even be the wind setting it off.

Worth a try, it was happening with mine for a while.

No bonnet switches
How would you go about checking the operation of the door switches?

I hope the earthing kit doesn't have anything to do with it - i might disconnect it for pure speculation!

I dunno if it still is the battery or not...cos it still seems to be a bit reluctant to fire in the morning?

well at least u know it has to be in the door circuit. (if thats definilty what the LED flash sequence says) u will need to either test it or disconnect from alarm system and see if it does it again.

does the interior light work ok with the door opening/closing?

really the best way is to do some testing (on the door circuit) with a multimeter IMO

coolio - thanks for all the replies
How should I go about testing the door circuit?...will endeavour to do some testing soon!

Try replacing your door pins, If they are old they may be worn out, or also check the point where the contact the door if the paint is worn back to metal it may be causing the pins to earth out and give false alarms..

Thx dude - will check it out over weekend