Centurion Vector2 User Manual page 29

Check the 'Mains Present' icon on the main diagnostic screen or switch
to the battery charger diagnostic screen and check the charger voltage
– right-hand value. This should indicate, 13.6V DC to13.8V DC, at
charge rate under full load of +/-1Amp. Each charger has a red light
(LED) to indicate mains supply.
Basic
maintenance
page 25