300E Alarm Premature Activation
 

My 1986 300E allarm will sometimes activate when I use the driver's door key and open the door, I then have to re-insert the key in either the trunk or the passenger to de-activate te alarm and then enter, it is random but can be done if you are fast when opening the door with the key and pulling the handle open, does anyone know of a timing adjustment or how to fix this ? I can deal with it but I have lent the car to family and gotten a call with the horn blaring as they try to use the ignition to de activate and go nuts :eek:

anyone ? still having the problem

The best way to fix these alarms is to unplug them:cool:

in passenger footwell- black box- two plugs. Unplug.

There is also a RED 12 pin connector down there (on right side)- that is the SRS system!

Jerry, great patience. You can always disable the alarm control unit, which is what most people do. The systems just get old and frail. Should be under the passenger front floor mat.

Answer
 

Factory Alarm System Issues
http://www.peachparts.com/shopforum/showthread.php?p=1143583













Have a great day.

i just unlock our 260e at the trunk

even if i unplugged the alarm...wouldn't lights flash?

I ahd the same problem, on 2 MB's unplug the alarm module 2 plugs and the problem is over, I don't think anyone will break ionto these old cars anyways. That is unless you leave expensive stuff laying around, the old system is that. OLD.

Wish I could be more helpful regarding your issue. I have the opposite situation, if I unlock my 300E using the key in the trunk lock the alarm sometimes goes off. If I need access to the trunk with the doors locked I have learned to unlock the car at the door first.