Crash/impact sensor location

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Lock
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Crash/impact sensor location

Post by Lock » Mon May 06, 2019 2:03 am

I'm putting a remote central locking system in and am trying to find the impact sensor - which with the OEM system would unlock the doors in a crash.
It's a positive trigger, but if I can find it I'll remove and ground the former + side which will trigger the door unlocks should I slam into something.
Does anyone know where it is because I can't find it. My Haynes says it's in the steering column but tracing wires I can't find it there.
Its trigger wire is in the drivers side door so I know it's there.
On an unrelated note, has anyone added a central locking control switch anywhere? Despite upgrades under the skin, I like to keep the cabin looking original. Wondering if anyone has installed a factory-looking button, and where.
1979 528i 5-speed conversion G260/6

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Mike W.
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Re: Crash/impact sensor location

Post by Mike W. » Mon May 06, 2019 11:18 am

Try just above or to the left of the glove compartment, but accessible. But I believe it's a rollover sensor, not crash, and only operates in the event of it being on it's roof.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter

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Lock
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Re: Crash/impact sensor location

Post by Lock » Mon May 06, 2019 9:04 pm

Thanks Mike, I'll look around there and see what it does when I move it around. But if it's only for rollover, and just unlocks the doors I don't know how useful that's going to be given the doors probably wouldn't open anyway due to frame damage and the glass would be smashed.
I'll use the wire for the indicator flashers so I don't need to run another from the door to console - then in a rollover at least it'll illuminate the indicators.
1979 528i 5-speed conversion G260/6

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Re: Crash/impact sensor location

Post by 528i-1981 » Tue May 07, 2019 4:27 am

If you're crossing through the dash anyway, you could use the dummy button where the rear foglight switch goes for your switch. Unless your E12 is euro-spec. My US-spec car has two breakers mounted on the knee panel for the fog lights. You could use push-type mini-switches instead. Another place might be the fader control for the stereo, if you're not using that any longer - you might need to look around for a panel-mount push-pull type switch that looks good.
(oo=00=oo) Eric
1981 528i Manual

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Re: Crash/impact sensor location

Post by 528i-1981 » Wed Jul 24, 2019 8:33 am

528i-1981 wrote:
Tue May 07, 2019 4:27 am
My US-spec car has two breakers mounted on the knee panel for the fog lights.
Correction - the breakers on the knee panel are for the electric windows.
(oo=00=oo) Eric
1981 528i Manual

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