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Re: Inertia Switch



<I have a 1979 Euro 635Csi.  In my glove box on the left hand side above the
accessory area there is a black plate.  On the other side of that plate is a
white tube about 6 inches long and about the size of a quarter.  On the end
of the tube is a switch that says Inertia Switch Ltd.  It pushes in or out.
 Any idea what it is?>

    It's the central locking impact sensor that unlocks the doors in case you
hit something with enough force-- I don't recall how many g's.  It's there so
rescuers can get you out without delay, on the premise that if you hit
something that hard, you're probably unconscious, or too injured or
disoriented to unlock the doors and get yourselves out.  The switch on the
end may be a system test-- you might try locking the doors and pressing the
button.

    I don't know when BMW started using this, but I was favorably impressed
to hear about it, and to have had it on my '81 528i.  I haven't heard of any
such device on American cars, for all their emphasis on "safety".  Some may
well have it; I neither know nor care, since I'm not in the market for one.

Happy Bimmerin'
Gary T
'87 535i, with power locks
'88 325is, with power bagels