Lots of thresads about that, including some solutions.
https://www.google.co.uk/search?q=Renault+megane+lighter+fuse&ie=utf-8&oe=utf-8&gws_rd=cr&ei=ZeICVYnvBYyEyQSx04CQCQ
XX
March 2015
Amy - it will either be the fuse for the lighter or the lighter itself - the bit you pull out - take it to another car and see what happens - a new element unit is quite cheap.
Good luck...
March 2015
I can answer this question...
Cigarette lighter not working but everything else is fine?
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