I think if your SAM module still good, you may activate the unwork component by reprogramming again. This call "CODING" using STAR DIAG to program.
Actually when we need to swap the battery, we must copy the SAM data to the STAR before disconnect the battery and load the data back to SAM module when new battery connected.
However if SAM module is bad, you need new SAM module and reCODING it again that should be done at Mercedes shop.
W203 C200K M111 2002
Denso Iridium IK20
Ground wires SARD