The Mégane II Owners' Club

My megane is the 1.6dci gt-line with stop start 2012 with 120,000 miles. The original battery was starting to fade and I got the battery low start engine message on the dash display. Purchased a direct like for like AGM replacement from Halfords and fitted it no problem. However I now have an orange warning on the dash saying CHECK VEHICLE followed by CHECK STOP & START. Needless to say the stop start is not active and the red light remains on the disable stop start switch. I guess I've been a bit of a dummy here and not followed a correct procedure. Everything else is working fine. Can anyone advise best course of rectification? I understand the software probably needs to be linked to the new battery but how? Many thanks Tony.

i have just done the same thing with the same result and from what i can understand the ecu needs to be told that the battery is new/ok and the stop/start reactivated. iv tried a off the shelf machine with no luck and i have been told a garage with renault diag software will sort it.