That is a little strange, we see a lot of A Class here & that is not a common issue from what you are describing!
First thing I will need is the car to be checked for fault codes - have you done this yet?
If not you will need to have the car checked & let me know what codes are stored.
Let me know how you get on.
Best regards, Paul
hi there have had a diagnostic done and thease are the fault codes i have been given
c 1200 brake saftey switch (redundancey)plausibility
070300 can signal brake light switch not plausible
well just to let you know replaced stop lamp switch and it compleatly cured the problem it hasnt done it for two weeks now cheers XXXXX XXXXX help