how to reset oil change message on renault megane cc

Try unhooking one side of the battery for a minute and plug it back on. It should reset the computer.

Unfortunately Renaults do not work that way. What you need to do is flick through the messages until you get to the one that says change oil. There will be either a thing to hold in on the dash or hold in the button on the end of the stalk. Hold either of these in, the message will start flashing, when it stops flashing you can release the button.
Hope this helps.
PS. l worked on Renaults for a year so this should be right.