MK3 alarm going off

[thatfatbloke]

Took the old girl for a short spin this morning,but when I got back the alarm would go off every couple of minutes whether it was locked or unlocked. Only way to stop it was to leave a door slightly ajar. I started trawling the internet to see if the alarm could be bypassed or switched off - it can't. Then I came across a thread on here regarding this problem and metallic objects in the centre console/armrest. It was then it dawned on me that I'd left my mobile phone in the centre console. 'Bound not to be that easy' I thought. However I removed said 'phone and hey presto,problem solved. Apparently the alarm sensor is in that area and leaving metal objects/phones there can result in the problem I and quite a few others have had. Strange but true.

[shanra]

I kept getting this and realised it was the same thing my mobile phone. It would also set itself off randomly when my car Battery was getting near the end of it's life.

[Malc]

I hate to say this guys but after many years of doing all the forum suggestions the old lady still, very occasionally, has a mind of its own and bursts forth with alarm noises ...........  but she settles down easier than before, or maybe she realises that " going off " doesn't irritate me as much as it used to and I just accept it !

Malc

[Cotswold Pete]

On 03/05/2017 at 5:35 AM, Malc said:

I hate to say this guys but after many years of doing all the forum suggestions the old lady still, very occasionally, has a mind of its own and bursts forth with alarm noises ...........  but she settles down easier than before, or maybe she realises that " going off " doesn't irritate me as much as it used to and I just accept it !

Malc

I had this with my Mk3, and also current Mk4, it's almost as if it is saying 'Do not take anything for granted now that I am getting on a little'!!!

Sometimes found opening and closing the moonroof did the trick, but maybe the LS was just tricking me?

[Dale_V]

Theres a proximity sensor that is cable tied to a support underneath the center console.

Open the center console lids, take out the center console storage, youll then see the sensor near where the cup holders are, cut the 2 cable ties, then simply turn the dial on the sensor anti clockwise with a flat blade screwdriver, re-attatch with new cable ties etc...

After owning my ls400 for 7 years, the alarm recently decided to go off whenever it wanted for some reason, so I knocked the sensitivity down a couple of clicks and its been great so far.

[runsgrateasanut]

Very occasionally, my alarm goes off when the Car is locked and I undo the Boot with a the key - not sure why?

[Malc]

pleased to tell you that my Ls400 is in for it's annual service and ( failed  )  MOT and one of the jobs was to sort out the Alarm Going Off syndrome ( thank you Dale V )  and my indy has found the under centre console adjuster and done just that ........  by the way it's made in France  ..............  and hopes that is the solution .... only time and occasion will tell !

More about my MOT in a bit

Malc

[Malc]

update ........  car's passed it's MOT and the alarm sound adjuster is just under the area where the cup holder is situated  ...  he tells me it's adjusted right down and will now only sound if the car is actually being opened without the key or remote locking being used  ( fingers xd )

Malc

[AndyCheltenham1]

My alarm decided to go off for no reason this afternoon and then again at 4 o'clock this morning-didn't stay on for long, maybe about 10 seconds, but enough to wake me up!!

Does turning down the proximity sensor(under centre console)  sort the problem or could it be something else?  The Battery is about  3 years old so should be ok.

Can the alarm just be deactivated to sort the problem out once and for all or will that affect the immobiliser?  I'm not bothered about having the alarm working as a theft deterrent I just want to stop it going off at anti-social hours and annoying me and the neighbours?

 

 

[dendonc]

31 minutes ago, AndyCheltenham1 said:

My alarm decided to go off for no reason this afternoon and then again at 4 o'clock this morning-didn't stay on for long, maybe about 10 seconds, but enough to wake me up!!

The lightening storm on Sun eve through the night affected many ground based things including some car alarms. I sat a running camera on a window frame & left it to film, the vid sound track crackles a bit in conjunction with some flashes of lightening, so, it was affecting some ground based electricals seemingly at random.

I once had a 'nuisance' alarm prob ('95 LS 400) & my indi disconnected the security system to stop it, so no security alarm, but, whose going steal a 20 year old car? so it was not a problem once disconnected.

[Malc]

my last post above refers and it's been a joy since NOT to hear the alarm going off erratically.

Malc

[Malc]

2 hours ago, dendonc said:

I once had a 'nuisance' alarm prob ('95 LS 400) & my indi disconnected the security system to stop it, so no security alarm,

I think my solution above keeps the alarm functioning ok ......  just keeps it silent otherwise  

Malc

[AndyCheltenham1]

I've got it booked in for Friday for the mechanic to sort out ( I did try and remove the centre console inner bit to get to the proximity sensor but struggled to get it out-if I carried on I know I would break something, I'm too clumsy to tinker with cars)

I've disconnected the Battery so at least it'll be quiet for the next few days