engine failsafe programme

[jkl141gp]

6/4/13
4.6is
engine fail safe programme came on,
battery level 12.4 when car is off
13.45 when charging
is it the battery, anybody experience this.
did a battery test on dashboard and battery level 11.6 this morning 11.4.
anybody experience this


its a oem battery marked 1412
dont know when previous owner replaced
anybody know what the stamp means