Relationship between Seat Belt Relay & Alarm System 1995 E320
 

What is the relationship between the seat belt relay, the interior light, and the alarm system on a w124 E320? My dome and my driver's puddle lamp will not operate ever by opening the driver's door. Also, the driver's door lock will not arm or disarm the alarm system (Nor operate the convenience window up / down sys.) However, all is well on the passenger side.

I'm sure about how the seatbelt relay relates to the alarm, but when this relay is shot, the dome light will not come on when the driver's door is opened. Also, you won't hear a buzzing noise when you leave your lights on and open the door.

O.K., thanks, but does that go for the pass side as well? Nothing works on the driver's door, but if I leave the lights on and open the pass door it buzzes.

Thanks!

Correct. The relay only affects the driver's door. If it goes bad, the dome light will still work when the passenger's door is open.