Hello!

I Just got a call from my girlfriend, saying that she can't get the factory alarm to disengage on my 123. Its supposed to disengage by using the key to unlock the driver's door. I'm not sure if she isn't turning the key all the way over or if there's actually a problem.

If it turns out there's a real problem, any ideas on what it may be? My first guess would be the mechanism in the driver's door lock that activates/deactivates the alarm, but maybe someone who knows this system better than me could say for sure.

Thanks in advance!

__________________
2001 VW Jetta TDI, 5 speed, daily driver
1991 Ford F-350, work in progress
1984 Ford F-250 4x4, 6.9l turbo diesel, 5 speed manual
Previous oilburners: 1980 IH Scout, 1984 E-350, 1985 M-B 300D, 1979 M-B 300SD, 1983 M-B 300D
Spark-free since 1999

Hello The Warden
Try trunk or other door to disarm alarm.
If this works, the driver door lock assy is bad.
If this fails, it is possible the key is bad, try your spare key.
If the spare key fails also, the security module may be at fault.
Have a great day.

__________________
ASE Master Mechanic
https://whunter.carrd.co/

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
2003 Volvo V70

https://www.boldegoist.com/

Tried the other door and the trunk with both keys (the original master key and a recently cut key), to no avail. I wound up disconnecting the box under the dash to get the car home.

There's an electric trunk lock that activates when the key activates the alarm (keeps you from being able to open the truck, even with the key). This is no longer actuating, as well.

Is "the box" under the dash the security module? If so, any idea where it can be gotten? I odn't remember seeing anything like that on Fastlane...

Thanks!

Hello The Warden
As far as I know, MB dealer only.
I was asking some questions earlier today.
The answer was that the module must be programmed to match your car.
It is possible that I did not understand correctly, I will check further tomorrow..

I had the same problem on my wagon. We took it to our mechanic who told us that it was probably smartest just to disconnect it because it would have to be replaced in order to be fixed.

i guess those boxes just go bad after awhile. i still have my alarm horn and box in the car, just disconnected. the box says "BOSCH"

The alarm would just go off randomly and it was impossible to turn it off.

let me know what happens.

__________________
1995 E320 Sportline Wagon "Bernard"
black on black leather

http://i.imgur.com/BdZ7jM3.png