Mercedes: turn signal, turn signals, safety flashers

Question
I have a 1999 slk 230.  when I turn on the turn signal in either direction or the
safety flashers the indicator light on the dash stays a solid green and does not
blink.

Answer
Shawn,
make sure that the safety switch is completely in the off position. If it is midway off it will interfears with the turn signals.
If that checks OK. You probably, will need to replace the flasher unit.
Or you have bulbs burned out.
The Flasher needs a certain draw to make it work. However, it sounds like the unit has gone bad.