On my daughter's 51 plate Fiesta the nearside light cluster has a buzzing noise when you switch the side lights on.
Investigating the problem there appears to be a green multi plug for the power which could also be a relay?

Has any had this problem ?...is there a relay in these Bosch lights ? can it be replaced or is it a new light cluster?...thanks Phil M

 

If it's a relay then it is possible that the conacts have worn and aren't making proper contact causing the buzzing.

I am not sure if they can be replaced to be honest.

 

Thanks....I think a new light cluster is required to stop this noise....Phil M