There is "SRS" lit up on my dash. Wat does it mean and wat causes it?

CD problem, common problem on your car,and don't think there is a fix,unless you replace the unit,very expensive! SRS stands for Supplemental Restraint System. If this warning light stays on in your Mercedes Benz, that means that there is a problem with the airbags or the components that are part of the SRS system. It is very unlikely that your airbags are going to deploy randomly, but the concern is that they may not deploy at all in a case of an accident. While your car will run with this light on, it is important that you diagnose this problem as soon as possible. The SRS system checks the operation of several components in your car such as: Airbags Airbag control unit Crash sensors Emergency Tensioning Devices Belt force limiters Child occupancy sensor in front passenger seat. Under normal operations, when you first turn the ignition and start the car the light stays on for about 5 seconds and then turns off. If the SRS light stays on constantly or you get Restraint System Defective Visit workshop warning or airbag light on, then you know you have a problem.