Well, after poking around in WIS, I located the infamous 'N26' box and it was indeed under the floor panel on the passenger's side.

I pulled it out, and problem solved.


Well, not really. I just had to crack the box open and see if I could figure out what was going on inside.

At first, it looks fairly complex, but it really isn't. The whole system is armed or disarmed by the state of a latching relay (it's the silver one marked Siemens).

I figure that since my alarm went off when I was driving, a condition that should never happen when the system is disarmed, the problem must be either in this relay, or the circuit that switches it on and off. So I pulled it off the circuit board. After testing with a 9v battery, I verified that the relay was in fact switching as it was supposed to. So, the problem must be in the circuit that switches it on and off.

What I am going to do to test this:


1) Solder 6 long wires in place of where the relay was.
2) Put the box back in the car
3) Arm/disarm the system and use a meter to verify that the control voltages to the relay are correct and adequate.

After this, I will hopefully know a little more about what actually failed. We were undergoing some VERY wet weather at the time, but the alarm box was bone dry, and the whole circuit board was varnished so not as succeptable to moisture as some would think.

The only thing that makes any sense short of the alarm itself failing is moisture getting in a door switch that arms/disarms the system.

I'll let you know what I find. I think this is repairable.


-tp