Sixto, thanks. Got it. Replaced the alarm, right where you said it would be, but the lights still aren't working. Anyone have any idea what could be causing the problem?

My previous post addressed finding the alarm controller. The factory alarm doesn't have a passive arming feature so it shouldn't change mode unless you use the appropriate key in an appropriate door lock.

86-up 126s have a central relay to control exterior lights. If there's a warning light with a light bulb icon in your gauge cluster, you probably have such a relay and it's probably bad. It'll be a 1" by 4" box in the engine bay fuse panel. If not, my guess would be a bad combination switch at the base of the turn signal stalk.

What's odd is lights flashing and horn beeping simultaneously. There might be an aftermarket alarm in your car. It could be anywhere. Is there something that looks like a small plastic bullhorn in the engine compartment? Maybe drop the panel under the steering column and look for non-factory looking wire bundles.

Sixto
87 300D

I was going to do that on my 300SEL, but it seems like that fuse controls many other things. Guess I will disable the entire system by pulling the plugs on the box. Do they simply pull out, or are there prongs to squeeze, or? Also, how does that panel come out? Just pull out?

The alarm started blaring/lights flashing on my '88 started when I went to unlock it today and it wont stop. Had to disconnect the battery and drive my Lexus today.

I knew it was too good to be true to have a properly working alarm on my W126.

I looked and it looks like a plastic nut, but I will have to buy a tool to do it. Does anyone know what size it is? I am going to get mad and rip it off if I dont soon find out.

[QUOTE=86560SEL;2142251] Guess I will disable the entire system by pulling the plugs on the box. Do they simply pull out, or are there prongs to squeeze, or? Also, how does that panel come out? Just pull out?
QUOTE]