problems with leisure battery

[Bessie the camper]

hello

ive got a problem with my leisure battery doesnt seem to hold it charge
when the engine is running im only getting 13.6V if i disconnect the charge wire i get 14.2V at the wire i have disconnected all outgoing wires from the battery and still the same so before i ring to claim under warranty i was just checking i was right

[R0B]

remove it.charge your battery for 24hrs.test voltage.leave it stood for another 24 hrs.test voltage again.if there is a significant difference in the two readings.your battery is not holding its charge.and needs replacing...