Z3 Alarm keeps going off. (1.9 - 2002) - want to totally disarm it

[Bobbybiscuit]

I have a problem with the alrm keep going off.

I have disconnected the battery for a couple of days. All was well when I reconnected it. Car ran a lot better. No alarm going off when I was driving. Got home parked it up and within 15 minutes alarm started to go off although i could turn it off on the fob. That was a bonus!!!

So i have read lots of things which includes taking off the lead to the bonnet sensor. Where is that located please so I can try that first.

Failing that how can i just have no alarm.

Where exactly in the car are the sensors for the alarm. I had a look and cant find them.

Any advice would be appreciated.

Cheers

Bob

 

[Rudyrov]

Alarms generally sense door switches that control dome lights, sensors that sense motion or impact and in some cases specialty sensors that sense proximity to the car, the later though are very rare.
in most cases the alarm is either sensing a voltage drop because a door was opened and te door switch has gone to ground or sensing a dedicated switch in the trunk or engine bay that is just a grounding switch.
your best bet is to seek out an alarm installer or find a diagram for your alarm so you know what is what.

 

[t-tony]

IIRC the tilt sensor is in the N/S/R well in the boot and often gets flooded. Also the actual switch on the bonnet can be problematic.

Tony.

 

[Bobbybiscuit]

I have accessed the boot and found the sensor (or nodule) under about an inch of water.Dried it out and i thought woohoooo it will work now. Well I took car for drive all ok for about 5 miles then suddenly alarm went off again when driving. Got car home. Reset alarm on fob and it was quiet for 2 mins and the started again. Reset again and it started again. If I disconnect it in boot qith that disarm the alarm? Thanks

 

[Ianmc]

My alarm issue some years ago was caused by the switch under bonnet (on slam panel). Suggest disconnect and see what happens.

 

[Bobbybiscuit]

My alarm issue some years ago was caused by the switch under bonnet (on slam panel). Suggest disconnect and see what happens.

Will go out shortly and remove it and see what happens. Watch this space.

 

[Varptr]

I have accessed the boot and found the sensor (or nodule) under about an inch of water.Dried it out and i thought woohoooo it will work now. Well I took car for drive all ok for about 5 miles then suddenly alarm went off again when driving. Got car home. Reset alarm on fob and it was quiet for 2 mins and the started again. Reset again and it started again. If I disconnect it in boot qith that disarm the alarm? Thanks

That was the same issue I had, water in the boot and a submerged tilt switch. Baled out the boot and never had a problem afterwards - except I still need to fix the leak!

 

[Bobbybiscuit]

That was the same issue I had, water in the boot and a submerged tilt switch. Baled out the boot and never had a problem afterwards - except I still need to fix the leak!

Removed switch in boot. Wires fell out off switch. The socket part totally seized in and green. So can’t connect now if I wanted to.

Hopefully that will solve my alarm issue. Fitted a tracking device today. So if it gets nicked it will tell me where my car is!!!

i have driven my car and has car standing so no alarm so far !!! As a matter Of interest does anyone know if the alarm is non functional now or will it still work with other sensors.

 

[Anfielder]

Remove cover from pass corner of boot, two ten mm bolts to loosen not undo fully. Slide mount and module off bracket and disconnect plug.

 

[Anfielder]

Remove n/s liner in boot ,loosen 10 mm bolts ,do not unbolt mount will slide off bracket .Disconnect module from bracket disconnect plug .Remove circuit board from inside module and clean with wd40 a tooth brush is just the tool, do the same to plug .Before you re connect remove grommet from bottom of well and with an 8mm socket ,punch a hole in plug. Then douse the well liberally with the babies dusting powder, at a later date after rain you will see where leak originates. Re connect and replace all parts mine works well ,Good luck

 

[Dado]

When returning home from a few days away (not in Z), a neighbour met me as I parked to inform that the alarm on the Z had sounded, 'Oh it's not going off now' the reply was through gritted teeth and was 'That's because the battery's flat' apparently it had being going for over 24 hours, reset, sound etc.
Had letters from the Council telling me to behave or else, letter from the Police asking me to phone them and explain and a few other neighbours calling by to ask if I have fixed it,
Read all the bits, disconnected the bonnet sensor, checked the boot, all dry, found a sensor behind the radio held by a cable tie, disconnected that, thought it was fixed, no more false alarms.
Took it to an auto electrician who disconnected a couple of other sensors but did not get it to go off so couldn't find any problem.
It was okay, for week anyway then it went into meltdown going off every time car locked by fob, so just locked with key in door, this does not activate alarm.
Eventually took to a local German car repairer who said... the alarm is part of the ecu and therefore not dis-connectable and he cured it by disconnecting all the remaining sensors and the sounder.
The alarm light still comes on to show 'armed' but obviously there is no real alarm any more but the ecu still thinks there is.
This may all be a load of testes, but occasionally I still get the indicator flash showing an alarm has gone off, no sound of course so no upset neighbours.
The ignition is still protected.
I must say I have never been much of a fan of car alarms, 99% of alarms seem to be due to faulty systems or people leaving the window open so much prefer a visual deterrent like steering wheel lock.