False Alarm

[Z4 - Kev]

The alarm on my Zed seems to have a mind of its own. It can be silent for hours then goes off without any reason. It then won't stop once I've turned it off with the key remote and armed it again. Also the indicators sometimes flash and sometimes don't when I arm it with the remote.
It's driving me nuts. Have to lock it with the key in the door lock most of the time.
Anybody else had the same thing?

 

[Stuartt]

Hi, possibly a fault with the bonnet switch as this seems to be the most common fault, unplug it and try that for a bit. It's in the middle at the back of the engine bay.

Also if you lock with the remote then press the lock button again the led in the rear view mirror will flash once and then it's locked without the alarm.

Stuart

 

[Lance]

Locking with the key/lock also doesn't arm the alarm.

What you describe was similar to what happened to mine.........bonnet switch for £11 from main dealer and 2 mins to swap over. No problems since

 

[Z4 - Kev]

Bonnet switch is first on the list then. Thanks.

And yes, I know locking up using key in door means alarm not armed ;-)

 

[85genius]

+1 on the bonnet switch worked for me, then shortly after I got my Z my mate got one and had to do the same on his.

I didn't bother replacing mine, don't need a sensor to tell me my bonnet is shut! Actually I think if you need a sensor to tell you that you probably shouldn't be driving in the first place.

 

[Steve84N]

The primary purpose of the bonnet sensor is to trip the alarm if a theft attempt includes snipping wires in the engine bay rather than to tell you if it's shut...

 

[Z4 - Kev]

I've finally got round to fitting a new bonnet switch. £35 from local BMW dealer.
Fingers crossed for no more false alarms.

Cheers for the replies above.

 

[Number5]

Does anyone know if the Bonnet Alarm Switch ( when bonnet shut) is :
- A Closed Circuit
- An Open Circuit
- a closed circuit with a specific tampered resistance, and if so what ohms is the resistance ?