need help, my kompressor is dead

[w208er]

Hi all, I have a CLK 230 Kompressor and now the kompressor unit is broken. actually it's only the coupling unit that shorted and burned. anybody ever experience the sam problem? do I have to replace th whole unit of the kompressor? or I can just replace the coupling unit only? Advice needed
for notes, my clk 230 kompressor 1998, and only 46000 km
Thanks before