Mercedes Alarm Control Unit

[SL man]

I wonder if anyone can help I have a problem with my alarm, when it is activated i can leave for a few minutes then it goes off. I have traced the problem to the control unit which is a becker one I have purchased a new control unit is there any particular way to instal it?

Thanks

[speace]

Mine was doing exactly the same. I will be interested in seeing if replacing the control unit takes care of the problem.

In my car, I have simply unplugged the control unit. There are two boxes side by side in the rear fender-well above the battery. On my car the first one was the door lock controller and the one further back was the alarm.

In answer to your question, I'm not a mechanic, but have an electronics background. It would be good to disconnect the battery while working on this. I noticed that my trusted shop did not disconnect the battery when they assisted me in troubleshooting mine. They just disconnected and reconnected the harnesses at the box... As I said before, I left mine disconnected.

[Florent31]

Hi guys. I am new but wanted to know how did you fix your alarm problem as I understand this is an old post. I experience the same issue with my 1998 SL500.Alarm going off about 10/20 min after leaving the car. Thanks for your support.

[97 SL320]

On my 97 SL320 , the alarm unit is in the right hand side of the trunk, near the fuel filler. I ended up unplugging mine due to it not disarming and having it alarm when I unlocked and opened the door. With the unit unplugged I lost remote unlock.

Be aware that 98 might have a different system as there were many electrical changes.