The Turn Signal and Brake Light may be operating from the same Bulb, or separate bulbs. Regardless, the Brake light filament must be burned out. Another option is that the Brake Light Circuit is on a separate Fuse, and the Fuse is blown. Check for those possibilities.
If your light is solid 1 bulb is burned out or if no lights blink it is a flasher located in your fuse box
A light bulb or a fuse.
If you are getting an indicator of a burned out light, but don't see a burned out light, it must be a turn signal light. On a Mercedes, you'll actually get a "burned out light" indicator if the turn signal is not working.
Check the signal light fuse, the signal light relay, and the signal light switcher.
The bulbs may be burned out, or a fuse may be blown.
under the dash in the fuse box
If the signal light fuse is blown all the signal lights front and rear would not work. If you have one signal light out I would first suspect a bad bulb or bad connection.
A blown fuse or burned out bulb
Burned out bulb Faulty socket and/or wiring/ ground Faulty turn signal flasher Faulty turn signal Switch
Fuse panel. Look in your owner's manual.
.