Hi,

I replaced the battery in my 2009 fiesta 1.4 titanium yesterday and ever since, the alarm has been going off (maybe every 2 hours?) and I think my neighbours hate me...

I've slammed the doors, bonnet and boot shut to make sure they weren't slightly open or anything, but it hasn't helped. Everything else works, the radio, windows, lights etc and it drives perfectly so I'm not really sure what could be causing it. As I mentioned, I changed the battery yesterday, maybe there is a step I missed where I need to let the car know somehow?

Any help would be appreciated greatly!

Not sure if this applies in your 2009 Fiesta, but do you get the option when you switch off the ignition to have reduced alarm coverage. If so, this deactivates the internal ultrasonic sensors. It’s designed to allow a pet or person to remain inside a locked car, but it prevents the likes of spiders activating the alarm. 

I'm not sure, where abouts would I get the option? On the central display? The infotainment on the 2009 ones is quite basic these days haha

2 hours ago, Carracer12 said:

I'm not sure, where abouts would I get the option? On the central display? The infotainment on the 2009 ones is quite basic these days haha

Not sure if yours has it, but my last 3 Fords have the option.  It comes up on the display in front of the driver asking if you want to apply reduced guard.

On 2/26/2021 at 12:23 AM, Edge of Reason said:

Not sure if yours has it, but my last 3 Fords have the option.  It comes up on the display in front of the driver asking if you want to apply reduced guard.

Yeah I think mine doesn't have it sadly, the central screen has very little to offer

On another forum I've had the suggestion that it could be a dodgy ground connection (meaning I need to clean the terminal) so I'll give that a go and report back in case anyone has this issue in the future and stumbles on this thread

So I've taken the battery out, cleaned the terminals and ends of the leads in the car. I've started getting the boot open warning now, so I've tried the trick of moving the U-shaped shackle up/towards me at the opening of the boot. It's still going off after WD40-ing the mechanism and so I'm lost really

What battery did you fit? The wrong type can sometimes cause strange electrical issues.

Hi, well odd things do sometimes happen at the same time. The replacment of the battery and the alarm keep going off might not be related. The big however is the fact the car is now saying the tailgate is open - that would set the alarm off without any problem. When you changed the battery did you have the boot open a few time to maybe get tools out ?

I think the real fault you have is the boot latch sensor if broken. I'm not familiar with the connections to the sensor on your car but they should be easy to find, normally two very thin wires going to a small black plug on the latch (means you will probably have to take the trim panel off the tailgate). Find the small connector and unplug it. Then on the half of the connector that is attached to the car wiring use something like a paperclip and short the two wires together. Now the car should stop saying the tailgate is open and the alarm will be neighbour friendly. TAKE CARE that it is the sensor wires that you short together and not the wires for the tailgate lock.

20 minutes ago, alexp999 said:

What battery did you fit? The wrong type can sometimes cause strange electrical issues.

I put my reg number into the Eurocarparts website and went with my only option:

https://www.eurocarparts.com/p/lion-063-car-battery-3-year-guarantee-444770631

Also the alarm was doing this in the summer so I think it might just be coincidental

3 minutes ago, unofix said:

Hi, well odd things do sometimes happen at the same time. The replacment of the battery and the alarm keep going off might not be related. The big however is the fact the car is now saying the tailgate is open - that would set the alarm off without any problem. When you changed the battery did you have the boot open a few time to maybe get tools out ?

I think the real fault you have is the boot latch sensor if broken. I'm not familiar with the connections to the sensor on your car but they should be easy to find, normally two very thin wires going to a small black plug on the latch (means you will probably have to take the trim panel off the tailgate). Find the small connector and unplug it. Then on the half of the connector that is attached to the car wiring use something like a paperclip and short the two wires together. Now the car should stop saying the tailgate is open and the alarm will be neighbour friendly. TAKE CARE that it is the sensor wires that you short together and not the wires for the tailgate lock.

That might be a good temporary fix, which will likely become a permanent fix! I didn't actually open the boot since I had tools in the house so I'm just confused really. The alarm was doing this over the summer as well but it stopped for 6 or so months, which makes me think it's unrelated

The boot switch was the issue, replaced at the garage, and hopefully never hear the alarm again

Good to know you got it sorted. 😀