If the motor did not spin you have
another problem. ( bad connection, batteries, controller,
key switch,
motor ect.)
If the motor spins there is a short in the throttle system.
Check all connections and look for broken wires.
Replace
Throttle
24V controllers will not have full
function when system voltage falls below 21 volts or each of two
batteries falls below 10.5V.
36V controllers will not have full function when system voltage falls
below 31.5 volts or each of three batteries falls below 10.5V.
SMART charging systems work the same way.
24V chargers will refuse when system voltage falls below 20.5
36V chargers will refuse when system voltage falls below 31.5 (
Ex. 44VDC output SMART charger refuse a 24v system)