As there is no indication about a degrading 12 volt battery like a struggling starter motor in an ICE, it’s condition that can bite you, and I am sure that is the reason for Renault advising replacement after 3 years. A bad 12 volt battery leads to the “Check Electrical System” dash message, talked about earlier here. It’s both a somewhat confusing message, and it seems to be not exclusively for a bad 12 volt system.
Today I noticed there is a field the EVC called “Battery 14v to be changed display”, with possible values “-“, “Soon”, or “Now”. That seemed to be a fine candidate to add to the 12 volt screen. It’s already on the development branch on github and will make it in the next release. It’s the 4th line called “Replacement advice”.
Feedback is appreciated! We’re interested to know if there is a CanZE “soon” message before the dreaded dash message, if the dash message corresponds to this CanZE message, and if so, whether the “12 volt battery symbol” (rectangle with two knobs on top) was also lit on the dash.