Take BMW 320i m sport e93 for example.
Symptom:
I‘ve
read through the book and tried the 2 second panic alarm, but nothing
happens, trying to open the boot no alarm and trying to open the doors
etc when locked, no alarm, when i lock the car there‘s no beeps..
However, when the car is locked and i go to open the bonnet, the alarm
goes off.
What to do?
The pre LCI US cars are
pre-wired for an alarm but the LCI US cars aren‘t. On post-LCI cars
it‘s almost always a factory installed alarm and on the window sticker
because the wiring harness is different.
I installed the alarm
on my pre-LCI as a "fun"project so it was not on the window sticker. The
car also needed to be re-programmed after the alarm is installed. When I
installed mine and before the re-programming, the clown nose - the red
light under the rear view mirror - blinked but most of the alarm
features didn‘t function.
The factory alarm preferences -
beeping and flashing on locking and unlocking -- are individually
programmable via the menus. IIRC it takes a few seconds after the car is
locked for the alarm to "set" and all the features to work.
If
the alarm goes off when you open the bonnet I think you must have an
alarm of some sort. The hood switch was one of the components of my
alarm kit. If your car did not have an alarm and a hood alarm switch,
the alarm could not go off.
Does the clown nose blink when you lock the car? If it does, you almost certainly have an alarm.
The
hood alarm switch on my daughter‘s Honda failed with the symptom being
that the alarm would randomly go off, sometimes in the wee hours of the
morning. Hondas are notorious for this and it was a big problem because
she lives in an apartment complex. Replacing the hood latch with its
integral switch solved the problem. IIRC it cost about $100 to have the
Honda dealer fix it. (It was in January and high temperatures were
running about 20F and I‘m getting too old for this.) As an aside, the
alarm was standard equipment on her Honda, along with floor mats, a
spare tire, a jack and a dipstick.
So if you do have a BMW alarm installed it must be a software or hardware issue.
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