e39 car alarm issues...

[Matt UK]

The car alram on my e39 has started randomly going off for no reason, which is very annoying.
I'm just going to disconnect the battery for 30 mins to allow the systems to reset. Problem is it has happened sparadically over the last few days.

Before I start paying people to run diagnostic checks on the electrical system, has anyone else had this issue or know why it would be doing it?
A mate said it could be a sign that the battery is on it's way out, but it seems fine - starts cleanly each morning and no error messages on the dash.
It actuall came back from a service last week and they comfirmed that no fault codes came up..

[TomM]

Disconnect the bonnet sensor, its on the right hand side mounted to where the suspension strutt is - had the same issue with mine.

[bramley]

Hmm, the chap on here that was generously giving out the spec and service sheets for BMWs said the only warranty work my E39 had received was a replacement bonnet switch (before I owned it). Sounds like they must be the cause of alarm probs then.

[Matt UK]

Bonnet sensor eh, I'll give that a go. Thanks chaps.

[Neil.D]

Definatley bonnet sensor.

[Matt UK]

What do we reckon - replace or just disconnect?

[Neil.D]

Just get a new one. Cheap + easy.