Electric vehicles are loved by consumers for their environmental friendliness and convenience. But when an electric vehicle develops a fault, many people are at a loss. Today we explain how to judge whether the trouble is a short-circuited controller or a motor that has taken in water.

With power off, the rear wheel feels very tight when pushing the vehicle

This problem is common. The usual symptom is that everything seems fine without power, but once powered on the rear wheel grips tightly and pushing the vehicle forward takes great effort. This situation may be caused by water entering the vehicle controller and burning it into a short circuit.

The battery shows full, yet the motor stops when the throttle is opened

The usual method is to connect the DC voltage range of a multimeter to the charger socket of the vehicle to check the battery voltage. If the voltage is normal when the vehicle is not being ridden, but opening the throttle makes the voltage fall to 42V and the motor shakes while its speed drops sharply, this is a battery problem. If, however, the fuse in the battery box and the wiring between the batteries are in good condition and, with the throttle opened, the voltage hardly drops while the meter shows the drop and the motor runs and stops intermittently, the cause lies in the ignition lock switch and its wiring. And if, with the throttle opened, the voltage hardly drops and the meter voltage also does not drop while the motor still runs and stops intermittently, then the current protection of the controller is at work.

The brake lever does not return and braking fails

It is common for a brake lever that fails to return to trigger the automatic power-off device; then no amount of throttle can make the vehicle run. Check the brake and work the lever back and forth a few times, and it will be fine.

How to judge: controller short circuit or motor water damage

If the electric vehicle will not move, turn the motor wheel by hand to feel whether there is any obstruction. If the vehicle rolls normally otherwise, the motor is fine and the likely cause is a water-wetted controller plug. Disconnect the battery, locate the controller, shake the water out, dry it with a towel, and refit it in place.

Clearing common spark plug faults

Common spark plug faults include electrode burning, overheating, and carbon deposits. Once a fault appears it directly affects engine operation, causing unstable running, power loss, and difficult starting. If the electrodes are severely burned within a short time, check whether the heat value of the plug matches the specified requirement; if the heat value is too low, replace it with a plug of higher heat value.