Dualtron Error Codes and Symbols: How to Read Them and What to Check
A symbol or error code appears on the display of your Dualtron, and the scooter refuses to move forward or is running at a very slow speed. Before searching for a code table on the internet, a precaution: the meaning of a code depends on the generation of the display. The same number can indicate two different faults on two different displays. This guide explains how to read the error on your machine, and then what to check for each type of fault.
The essentials
- The latest EY3 displays on Dualtron scooters often only show a maintenance symbol; the details can be found in the Dualtron app.
- The issues can be categorized into several families: throttle, motor, controller, temperature, battery, and communication.
- Only take a code table seriously if it matches your display and your model exactly.
- For each family of products, we first check the connectors and cables, and then the individual components.
How to read the error code on your Dualtron
Recent displays: a symbol, and the application
On the latest generation EY3 displays, the Dualtron documentation indicates that in the event of a malfunction, the screen only shows a maintenance symbol. The specific error code can be found in the Dualtron app, which connects to the display. The app categorizes errors into broad families, such as the throttle, motor, controller, or overheating.
Older displays: a coded system
Older displays show an error code. The list of codes depends on the display model and the scooter version; the only reliable reference is the manual for your specific machine. Lists circulating online often mix codes from different generations.
Note the error code or error family, the moment it appeared (startup, acceleration, after prolonged use, after rain), and then refer to the corresponding section below.
Throttle malfunction
The controller is receiving an abnormal throttle signal: it may be absent, too high when at rest, or inconsistent.
- Check the throttle connector and the cable that runs down into the steering column, as it is often pinched or worn at the bend.
- Ensure that the throttle returns to its zero position properly and that it has not become stuck or jammed.
- Consider the water: a water sensor or a damp connector can send false readings.
Motor fault
The controller is not correctly recognizing the motor: it's not detecting the position sensors, phases, or temperature of the motor.
- Inspect the phase connectors (three large wires) and the sensor connectors (thin wires) at the motor or arm: a blackened connector or a bent pin is common.
- Test the Hall sensors with a multimeter, as explained in our guide on how to fix a scooter motor that stutters or jerks.
- On a Dualtron with two motors, check to see if the fault is specific to one of the motors.
Controller fault
The controller is reporting an internal problem or a condition that it is unable to handle.
- Look for any signs of water or corrosion inside the controller compartment.
- Check the power cables connected to the controller and verify the battery voltage both at rest and under load.
- On a machine with two controllers, a fault on one controller should direct you to investigate that specific controller or its wiring.
Before replacing a controller, rule out less expensive causes first, as they are more common.
Overheating
The controller or motor has exceeded its temperature limit. Power has been reduced or cut off to protect it.
- Allow it to cool down completely before restarting.
- Consider what might have caused the overheating: a long uphill climb, a heavy load, a more aggressive setting, or a controller with inadequate ventilation.
- If overheating occurs during a normal ride, a temperature sensor or a connector may be the cause.
Battery and voltage
Low voltage, excessively high voltage, or a defect in the battery itself. A complete shutdown with the display turned off is most often caused by the battery's Battery Management System (BMS): see our guide battery and BMS that cause shutdowns.
If the battery in your Dualtron is wearing out, our workshop offers replacement batteries for Dualtron, including performance versions.
Communication
The display and controller are no longer communicating. The scooter often gets stuck and won't start.
- Check the cable connecting the display to the controller, paying particular attention to the area around the steering column and where it bends.
- Check the connectors on both sides, and don't forget to check for moisture.
- A display that has been replaced with a model from a different generation may not be compatible with the controller.
Workshop tip
Always note the exact error message and the circumstances before turning off the scooter. A fault that disappears after restarting often reappears, and these notes can save a lot of time during troubleshooting.
The case of modified Dualtron scooters
On a modified Dualtron (with a more powerful battery, different motors, and different controllers), the original error codes may no longer apply. An adjustable controller like the VESC records its own fault codes, along with the current and temperature values at the time of the error. This is often more precise than a display code.
Frequently Asked Questions
My display is only showing a single symbol, with no error code. What should I do?
On newer EY3 displays, this symbol indicates a maintenance requirement. The specific details of the issue can be found in the Dualtron app, which connects to the display.
Can I rely on the code lists found online?
With caution. The meaning of a code can vary depending on the display and the generation of the scooter. A list is only valid if it exactly matches your model; otherwise, use it only as a guide for your checks.
The error disappears when I restart, does that mean it's fixed?
Not necessarily. Many faults are intermittent: a loose connector, a cable that breaks at a bend, moisture. If the error reappears, you need to investigate the cause.
The problem only appears on one motor. What should I check?
The motor in question, its phase and sensor connectors, and the controller that drives it. On a dual-motor machine, comparing both sides is the quickest way to identify the faulty component.