Possible
causes:
The battery voltage is low or the battery is faulty or disconnected
There is no mains power to the motor
Faulty controller
Possible
solutions:
Measure the battery voltage – it should be no lower than 11V DC when placed under load.
Check for corrosive build-up around the battery terminals. If there is corrosion, replace both the battery and terminals
Replace the battery
Measure the onboard charger’s output voltage. It should be about 14V DC
Ensure that the safety PE beams are in working order
Replace controller