2004 Mercedes Benz S430 outside mirror turn signal light/le

For the mirror signal the light itself is replacable, you do not have to replace the mirror assembly. You must remove the mirror to access the mounting screws. This accomplished by pushing the mirror down and looking behind it. You will see a small metal wire tab. This holds the mirror on. With a small screw driver pull it back and remove the mirror. Behind the mirror motor you will see the back of the turn signal. There should be 3 torx style screws holding it in. Simply remove and replace and the warning will reset itself.

As for the Tire Presure monitor, these are terrible systems on this model and go out all the time. Everything from sensors to control modules to antennas go out on this system. If you have no pressures coming up you are probably going to have to bring it in. A side note; when this system came out (TPS) us at the dealerships were swamped with these types of failures.