I've come across this information once too often on this forum but can't find anything for my car.If I remember correctly, it was Benzmac who had the duty cycle fault codes though I also forgot the car he was discussing, 124 or 201...

You could get luckier coz your car is similiar to the ones in the US so the guys on this forum may be able to help.

My model is similar to the Aussie and UK version so I guess I should search in those areas.

Good luck, buddy.