Hi,

I have a 2009 mondeo mk4 estate I have had the car for 7 years. last year at the start of lock down the alarm started going off at random times. To reset, you just open, put the key and turn on the ignition (dash board message will sometimes come up saying 'alarm triggered') then remove the key and re-lock the car. Also occasionally the dash says 'rear nearside passenger door open' (this meeasge can last a few seconds or all day), but always clears.

I have tried to find the cause of this alarm problem. firstly I deactivated the internal sensor, Then I had the alarm module removed as another message appeared saying 'alarm service required' (this is located under the front wheel arch), which was only the back-up alarm so made no difference to the alarm going off! Then I removed the anti-theft alarm fuse and relay (they are located behind the left hand panel in the boot, this had no effect the alarm still goes off!

Has anybody else experienced these problems, could it be related to an intermittent fault with the nearside passenger door lock?

Sid57

 

It sounds like the fault with the nearside door is triggering the alarm, it's detecting the door is either open or unlocked. 

I'm sure someone will be able to offer some advice.

Could be a problem with the connectors or the wireing

Bonnet catch is often the cause, you can easily by pass the catch just unplug the connectors and Ben a bit of wire to fit into the connector, it may or may not be the cause but it's an easy on to eliminate.