Alarm keeps going off?

Hi,

I bought a 2006 z4 in October last year. Since about march of this year the alarm has been going off by itself regularly. I almost always leave it with the top up when parked so I don't think it's leaves or something falling into it. I'm at a loss as to what to do next. Normally the alarm problems start within an hour after it being parked. When it happens I unlock and relock but within an hour it'll happen again. This will go on for a few hours before it stops. However this morning it has started going off even though it hasn't been touched since yesterday afternoon. I wonder if temperature changes might be part of the cause?

Can anyone offer some advice about anything else I should check before I take it to the dealership?
 
Bonnet switch, just unplug and you should be fine it's near where the 2 strut supports meet on the the bulk head
 
Mine did the same when I purchased my Z and I followed the advice like Mark has given and got a new sensor from Sopers of Lincoln and swopped them over and it cured the problem :thumbsup:
 
Same thing happened to mine & it turned out to be the battery getting a bit low. Tried the bonnet switch first but it made no difference. Even though she started & ran perfectly after not being used for a couple weeks the alarm started playing up. I tend to put her on the Ctek now if she's going to be parked up for a while & I've had no issues since.
 
Useful info. My alarm has been known to randomly activate. Pretty infrequent and pretty sure it's is when the battery is low.
 
Ian.newson said:
Thanks everyone, I've disconnected the sensor and it hasn't gone off for over a day so hopefully that's it.

Good news then - and by the way, welcome to the forum. :thumbsup:

But now you've joined we do like to see a photo or 2. :lol:
 
Of all the Z faults, I believe the bonnet sensor’s the number 1 that goes wrong - brought me here & appears as a regular post

Good to hear all quiet, definitely a cheaper fix than a new battery
 
Ian.newson said:
Thanks everyone, I've disconnected the sensor and it hasn't gone off for over a day so hopefully that's it.

Think it's a common fault....I had it going off on mine randomly for while - Had only just moved into a new house when it was happening at 3am most nights so was a fun way to introduce myself to the neighbours! :oops:

Easy and cheap fix, think it was about a tenner for a new one off eBay and then a 2 minute job to replace it and plug it back in - touch wood hasn't happened since
 
Back
Top Bottom