Car alarm going off at night... Possible cause????

[KCarter90]

Hi all,

As the title suggests i'm having a problem with my car alarm. For quite a while now I have been disconnecting my car battery every evening just to ensure that my car alarm doesn't go off at night and wake the neighbours.
I've become a bit complacent with this and it's just become a normal routine.

I recently took my car into a garage for a diagnostic for an unrelated repair and noticed that listed was a faulted with the immobiliser.
I've had a quick google search and from what i can see it might be a problem with the battery in my key fob....

Could this be why my car alarm is going off at random??
I've attached an image from the diagnostic report


Thanks in advance for any assistance.

Kyle

 

[KenGMac]

Some vehicles have a warning light on the dash that tells you if the key battery is low? have you seen any indications?

Change the key fob battery, generally a CR2032, at least mine is

Suggest you purchase from a Supermarket, my local "Spares" outlet sells them but not a decent quality version.

 

[johnny2007]

What vehicle?

 

[freddiemercurystwin]

Vauxhall Astra sri ctdi, 05 plate, Diesel

 

[johnny2007]

Vauxhall Astra sri ctdi, 05 plate, Diesel

Have you got 2 usernames?

 

[dontbelieveawordofit]

.

 

[dontbelieveawordofit]

.

 

[johnny2007]

that’d be a first...... most on here have at least 2.

What? Why? Who?

 

[Burnerman]

Flies trapped inside are an issue in summer, occasionally spider intrusion at other times.
I’d close all of the air vents and tape over any ultrasonic sensors the car has.
John

 

[freddiemercurystwin]

Have you got 2 usernames?

https://www.diynot.com/diy/threads/alternator-replacement-oil-issue.539025/#post-4554710

 

[HERTS P&D]

Shock/Horror, another Vauxhall thread

Andy

 

[ericmark]

Many years ago I worked as an auto electrician, and we fitted car alarms, and the method it used to detect a door being opened was volt drop as inertia lamp came on. This worked OK with most cars, but some it caused problems, and as luck had it one guy with a problem was mate of the boss, so we tried swapping on a temporary basis the battery. And it worked. We started fitting a different make that did not monitor battery voltage, clearly trying to tell customer the fault was the battery and he would need a new one so alarm would not random sound was not going to work.

With my Kia every so often one of the doors does not close fully, and the door open warning light comes on, so I stop open and close every door, and no more problems, however in lock down taking wife to hospital and had to wait in car, and every so often found a gust of wind could cause warning light to come on, sitting with ignition on listening to radio. Had the alarm been set, this would have set it off.

With factory fitted alarms they are all the same, and in some cases the alarm can actually be used to help steal the car, early Range Rover had this, you could reach under front, release bonnet, and then bridge to wires on the alarm module to open door and turn on ignition. Likely could also do with after market alarms, but they are all different, factory fitted all the same. Sure cured now, but not keen on factory fitted alarms as a result.

Best anti-theft is drive a cheap car no one wants.