I take it your Megane has air con?!
Remove O/S/F kick panel (the plastic trim by the throttle pedal) behind there you'll find a big block connector in the wiring loom, you'll find that the earth terminals have melted, may of even melted to the extent that you can't seperate the connector!
To rectify the problem simply cut the earth wire either side of the connector and solder a piece of wire of the same gauge as the original wire to join the two cut wires together completely bypassing the connector - job done!!
Stuart - former Reno tech.
December 2007
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