it never did tis b4 until 2day ive had the car 6months now

could it be so at night you dont have a bright light on in the car and get dazzled

The main lights draw more current. That is why your main lights dim if you start your engine with them on - the starter motor hogs all the power.

l can assure you, its always done it. you have just not noticed it.

they go dim so that at night, you are not dazzled by the dash lights if they were as bright with the lights off. all renaults do it.

the battery is about to go or the alternator is packing in is it starting to struggle on cold mornings get it checked if you really rely on it

Dash lights can be dimmed. You've probably turned the dimmer switch down accidentally. Turn it back up again.

more than likley dash clocks are in thr early stages off going faulty .. l work fo rrenault in ireland and we are fiting loads off dash clocks every week .. get them checked out .