Mercedes-Benz windscreen wiper fault - can you recommend a specialist?

I recently bought a 2005 Mercedes-Benz S320 CDI showing 50,000 miles. I am very pleased with the car with the exception of the windscreen wipers which sometimes don't work. I have twice been to the local main Mercedes dealer, but they were unable to find the fault.

They are reluctant to contact Mercedes-Benz in Germany, claiming that they would only tell them to do more of what they are already doing and incurring more cost to me. Is it possible that there is a local specialist who can remedy the fault?

Asked on 27 October 2012 by GM, Colchester

Answered by Honest John
It's a fault I've never heard of so I have no idea who specialises in fixing it. Our 'reader recommendations' in your area comes up with: good-garage-guide.honestjohn.co.uk/garages/m/merce.../

If you are prepared to travel to London, these people have a fantastic reputation: good-garage-guide.honestjohn.co.uk/garages/d/dna-t.../
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