Do you have a VOM? Checking battery voltage and continuity could give a few hints.
FWIW: Sounds like a few dead cells in your battery<s>. Your controller may have under voltage protection to shut off power before the batteries get drained too far. i.e. a 24V system will shut down at 20V or a 36V system will shut down at 30V.
With no drain the system may have been just over the minimum voltage and as soon as you turned on the throttle, the motor clicked, drew a bunch of amps, voltage dropped below minimum, system shut down.
Dead cells are a chemistry thing. For example, lead acid battery use lead oxide and lead metal with a sulfuric acid electrolyte. When the battery gets fully discharged, insoluble lead sulfate forms which more or less kills the battery. Just about every battery type has its own mode of failure. Anytime you leave a battery alone for over 2 weeks you run the risk of premature death.
The more bad news is: You should never charge a system with a dead cell. What happens is the bad cell can act like a dead short so instead of a 24V battery pack it is now a ~21.9V battery pack. Your charger still tries to charge your battery pack to 24V so it over charges everything and cooks the batteries that are left.
FWIW: Sounds like a few dead cells in your battery<s>. Your controller may have under voltage protection to shut off power before the batteries get drained too far. i.e. a 24V system will shut down at 20V or a 36V system will shut down at 30V.
With no drain the system may have been just over the minimum voltage and as soon as you turned on the throttle, the motor clicked, drew a bunch of amps, voltage dropped below minimum, system shut down.
Dead cells are a chemistry thing. For example, lead acid battery use lead oxide and lead metal with a sulfuric acid electrolyte. When the battery gets fully discharged, insoluble lead sulfate forms which more or less kills the battery. Just about every battery type has its own mode of failure. Anytime you leave a battery alone for over 2 weeks you run the risk of premature death.
The more bad news is: You should never charge a system with a dead cell. What happens is the bad cell can act like a dead short so instead of a 24V battery pack it is now a ~21.9V battery pack. Your charger still tries to charge your battery pack to 24V so it over charges everything and cooks the batteries that are left.