mahina na siguro talaga yung battery ... charge to experience na lang ... palitan na ang battery
ganunpaman, siguraduhin na matino ang alternator (kahit na malamang ayos ang alternator kasi bago pa) ...
note that some alternator fault may or may not lit the warning lamp ... with such trouble, i.e. internal short on rotor windings is one example and charging is insufficient, you will still experience low bat after a few days even with a new battery ... even faster (to low bat) if you drive at night
