manikki

My alarm keeps activating for no apparent reason.
For a few months the display has told me that the bonnet is open when it has not. I have found forums linking this to alarm problems but replacing the sensor is expensive so I want to be sure this is the reason, if possible.
The reason I am not so sure is that the alarm problem has only occurred the last week.
I lost my key for a day so I had to use the none remote key which I have never done before. That day was a nightmare as the alarm went off even when I left the car unlocked and I had to leave the key in the ignition turned to II, and keep an eye out of the window at work.
Since then I have only used the remote key. Sometimes I lock it and it is fine other times I lock it and after a few minutes it goes off and keeps going off no matter what I try until it is next driven and then it is about 50/50 as to whether it will happen again next time I park the car.
Any ideas?

Cardie

What car is it? Would be a good start haha.

manikki

Sorry, having a blonde moment. (thats my excuse any way)
It is a focus c max ghia 1.6 deisel 2005.
Think it is a MK 1 but could be wrong on that.

bluescortcossie

i'm assuming its a standard fit alarm , as you have already had a bonnet open warning its worth checking the bonnet switch as this is a common fault and while you are at it check the doors switches (i cant remember if its a plunger type or built into the latch on the bonnet though)

another common cause is a low battery voltage , check its holding a good 12+ volts and the terminals are tight

gcfcos

Check Bonnet switch. Sometimes we disconnect car battery's for a few hours and then reconnect them and it seems to re set some cars