its the engine management light telling you that there is a fault, the most common on the Megan petrol is the individual coils braking down, best thing to do is have a diagnostic done to confirm this and then buy a set of 4 coils from G.S.F. motor factors (hell of a lott cheaper than Renault) P.S. its best to change all 4, if one is faulty the others wont last long
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