Use the normal setting. EFB do not need the higher voltage as AGM need.What kind of charging program did you use?
I hooked up a charger the other day and put it on the regular lead acid charge setting. Then I got to thinking that maybe the EFB battery that the Gren has, uses the AGM setting instead.
My charger doesn't have an EFB setting.
After a couple minutes of Google sleuthing and (gasp!) reading the owner's manual, I can't find what charge setting to use.
The manual is silent on the matter and google just says to use the proper charger for an EFB battery.
I finally unhooked the charger and put it away. I figure I'll et the car charge itself as it sees fit.