Question about 1987 Mercedes-Benz 300-Class

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The security system keeps going off in my 1987 mercedes 300e. using the key in the drivers door doesn't work to turn it off. can i remove the fuse to disable it for now? if so, where is it located?

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Probably a dirty micro switch which is built into the driver's door lock. I believe you could verify this by using the key in the passenger front door or the trunk lock. Either of these, which are used much less, should unlock the doors without sounding an alarm.

Most people unplug the alarm module which is under the floor mats in the front passenger's area. If you want to try to clean the switch, a aersol can of tuner cleaner/lube from Radio Shack, will probably restore the function of the micro switch. Mercedes is notorious for using silvered contacts that tarnish just enough to hinder continuity.

Jim in Phoenix

Posted on Jan 24, 2009


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