How does BMW alarm work?

[DRWWE]

A couple of weeks ago I stayed at a hotel with a large parking garage. I parked my 745i parallel so I wouldn't get dinged. The space was right next to the main driveway so cars would be passing closeby. The space was well lit and had fairly heavy traffic so I thought it would be safe. The space was also between some posts so no one was parking directly in front or back of me.

When I went to retrieve the car the following morning the red light on the rear-view mirror was flashing so I assume the alarm was set off. The car looked fine and I could see no evidence of tampering. So either someone tried to get into my car or something passing closely set it off. It made me curious about alarms.

What will and won't set off the car alarm in these cars? I know there is a motion detector. I've bumped into the car in my garage an nothing happened. When I had my 530 the alarm went off once when I parked to close to where the helicopter lands at my hospital, so there is something to detect vibration.

 

[MyHarley]

I don't know about the newer models, but my 7 and 3 Series both have the nose flashing when the alarm is set. It should always be flashing as this signals to the owner and others that an alarm is in effect.

 

[DRWWE]

Sorry, I meant the rapid flashing which indicates the alarm went off. I am just wondering if a closely passing car could set the alarm off or if someone really did try to break in.

The alarm on my 7 has gone off a lot more than my previous 5. I know it's more tempting to break into, but it's going off in places where I expect it to be very safe, so am wondering how sensitive the car's alarm really is and what can set it off (I'm aware of the tilt and interior motion sensors and yes, I've read the owner's manual). There have never been any visible signs of tampering with the car.

 

[MyHarley]

My 7 does have a more active alarm due to gusts of wind or large passerbys that cause it to move. I've stood in the parking lot and watch the alarm go off after movement has occurred due to these reasons. Of course when I left my puppy in her car seat and ran into the store to get a paper, she set it off too.........and BTW before someone blasts me it was 57 degrees and she has two blankets.

 

[CosmosBlack]

A friend of mine who had a E36 328i, had an over-sensitive alarm which would go off in the middle of the night for whatever reason, cats maybe?
So he took it to the dealer and they adjusted the sensitivity, solved the problem.
You might want to check with your dealer on that.

 

[tool fan]

Nuclear Fission???




Sorry I had to. lol