My alarm keeps going off?

i have a 53 plate frontera and for ages the alarm goes off on its own but after reading a few of these messages and it lead me to disconect the power sounder (under passenger side wheel arch on my vehicle) and since then ive locked it every night with remote and its been perfect, all i did was disconnect it with the ignition turned on

steve
August 2010

Try isolating the interior sensors to see if it solves the problem.
Often it is the power sender batteries which need changing under the nearside wing.

Peter
December 2009

The easiest - but most expensive - thing is to take it to a dealer or independent garage with good diagnostics equipment and people who know how to use it. They can read the alarm activation log and find out which sensor or circuit is triggering the alarm.
There are a few checks you can do first.

Make sure all doors, tailgate and bonnet are properly closed.

Did the car give an occassional little "beep" for a few weeks before this started? If so it's probably the battery in the "power sounder" unit failing. It's not practical to replace the battery, the unit is best replaced.

Is the car battery in good condition and fully charged? If the alarm senses a power drop it assumes the car is being tampered with. Make sure things like the boot light and glove box light are not staying on.

Has anyone been working on the car? Make sure the bonnet switch is correctly adjusted. I'm not sure where it is on your Frontera but on some it's easy to bump or lean on the switch.

Have you "decorated" inside the car at all? Hanging air fresheners, badges etc. can set the alarm off.

Is there any common factor, eg. when the car is parked in a certain place, after opening the doors, a certain length of time after locking etc.?

hal
May 2009