Renault Repair Questions? Ask a Mechanic for Answers ASAP
What model of Renault? ie:- clio? , megane??
Id still inspect the brake pads for good measure anyway..ive seen this fault appear on several Renaults..and all bascially required a brake pad change because as the pad wears, the piston on the callipers needs to travel further..and this means the level will drop slightly triggering the level sensor to send a message back thinking the brake system has a leak..which isnt the case of course..so obviously thats one common thing to be checking..also ensure your brake lights are working..if an intermittent faulty brake light switch is going faulty then againthat trigger that too.so have someone at the back whilst you operate the brake ensure your brakes light are "all" working...
If its not handbrake/parking brake warning then you can discount that being at fault..but they can be known well across the renault range that use electronic parking brake to suffer issues.but you would need to have it plugged in diagnostically to see if the problems associated there..but as above the first step if you havent done so already wuldbe to get the pads front checked and brake on the back too checked for wear..hope this helps