I would say batteries are shot and your battery charger is shot . See if you can start your engines and see if your alternator can power your lights up ? Some thing is not working right.
Even if the batteries are dead, the battery charger should be able to push amperage through the batteries to the 12v system.
With the battery charger turned on, take a volt meter and see how many volts is being sent to the battery. It should be above 14V. It should certainly be above 12. That may be the reason the batteries are dead.