95 300E will not start

I have a 95 300E Diseal and it will not start. Whenever I turn the key to warm up the glow plugs, there's an alarm that goes off, which by the way is a really annoying sound. When I try to start it, there's nothing... not even any clicking noise from the starter. Any ideas to what it could be?

No fuel pressure. it might be bad fuel pump relay. Can you hear the pump running? or no ignition spark, - it could be a bad coil. DME problem or bad mercedes rotor arm. Sometimes loose connections or dirty wirings can cause this problem. This are only some of the possible causes. It would be best to check all your car parts to see what might be the real problem. By the way, have you done tune-up lately? 

The car is a diseal so there's no electric fuel pump on it and I havent done a recent tune up on it