mercedes benz, 2014 e class , rear left led light has stoped working.

  mercedes/e-class/2010-2016

Hi guys, I own a 2014 e class.

Yesterday i realized that my rear left led light would not light up(although the indicator+stop light still work)

I went to my mechanic to see what could be done, and the solution that he said was the only one, is to change the whole light (that costs around 400 euro = $500) 

i thought it would simply need a new bulb.

can anyone please confirm that this is actually the only solution.

I thank you all  in advance

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