Alarm going off when driving

[alan36]

As above really. The wife is out with the car at the moment and the alarm is going off while she drives, what is wrong peeps.

[BladeRunner919]

Depending on the alarm, if you press the unlock key when the car is unlocked, it triggers the siren - a panic alarm kind of thing. Not sure if it does it with the engine running, but sounds like that's the problem. Maybe the fob is faulty if she's not actually pressing the button.

[Robert T]

Which alarm do you have? The one with the housebrick remote or the one with the buttons built into the key?

Cheers R.

[alan36]

Buttons on key

[Robert T]

In which case, the alarm should be silenced by putting the key in the ignition - this works even if the battery in the key goes flat.

Is the light on the key permanently on? If it is then this may be the problem, in which case remove the battery from the key.

I note from some of your earlier posts you have had some electrical problems with the car, so it could be an electrical short somewhere. First thing I'd check though is water in the tilt switch in the well on the passenger side of the boot (behind and below the trim). It could also be the boot lid wiring, as this goes to the boot lock and boot open switch, which are both linked into the alarm.

The only other though I have is the siren - on this alarm they normally die silent, but it could be that yours has developed an internal short. The siren is not particularly accessible, so disconnecting it not really an option until you get the car home. There is no key switch on this alarm either, so you can't turn it off as you could with the earlier alarm system.

Cheers R.

[Jewell]

Yep, I'd go for this one as mentioned:

First thing I'd check though is water in the tilt switch in the well on the passenger side of the boot (behind and below the trim).

exact same thing happened to me in my 1.9

[alan36]

Can I just dry it out and all will be well?

[alan36]

Would the water ingress still be the fault although the alarm isnt even armed.

[Robert T]

GUYS YOU HAVE THE USA SPELL CHECKER LOADED ON HERE!!!

Really? My spelling checker is a part of my web browser and it is set to British English.... favour, flavour, endeavour.... yup, British English.

AFAIK the immobiliser operated independently of the alarm, with the caveat that on the later alarm, the immobiliser can unset it.

There are a number of things you can try with the tilt switch - first of all get rid of the water, if it works good, if not, it may be fried - if it has a connector on it, then you might be able to unplug it, and hopefully the alarm with then ignore it - if you can remove it, then I would bring it into the house and put it somewhere warm to dry out (airing cupboard). You also need to sort out where the water is coming from - third brakelight, aerial grommet and bootlid wiring grommet would be prime candidates, followed by the back of the roof.

Cheers R.

[alan36]

Thanks Robert, just one more question, what does it look like

[Robert T]

Thanks Robert, just one more question, what does it look like

It looks like this:



Sorry, but I don't have a better view of it. Next time I go in there, I will try and take a decent pic of the tilt switch itself.

Cheers R.

[alan36]

I have now checked in where the tilt switch is and it was a puddle of water and the 3 wires that go into the connector had basically corroded and fell off. I removed the tilt switch and the alarm was still going off. I have now disconnected the battery which seems to have stopped the alarm.

Is it possible to completely disconnect the alarm and not have it working at all and if so how do I do it.

Alan

[Robert T]

Unfortunately the gradient sensor (as BMW call it) is not a simple switch, otherwise I was going to suggest which connections should be open/closed. You are going to need to reconnect the broken wires. Can you managed to get a closeup of a) the connector on the gradient sensor and b) the wires leading to it. Assuming I have the right diagram, the module appears to have 5 connections and I can tell you which colour goes to which pin.

I do not know of any way to disable the alarm or alarm siren on the later alarm, short of disconnecting it (and I'm pretty sure it won't have a connector you can unplug on it). It is also buried somewhere under the fusebox I think.

Note: I have merged this topic with your earlier one, as it relates to the same problem, so it would be good if your findings are put with the problem description.

Cheers R.

[alan36]

Can anyone tell me if I can just cut the wires to the siren box and just not have an alarm or is there more to it than that.

[alan36]

Can someone help me please

[M3BMC]

Hi Alan, did you sort this issue out as I have similar problem at the moment and suspect the tilt switch due to water ingress. Cheers col