Electric scooter error codes are designed to protect the system and inform riders of abnormal conditions. When an error code or warning icon appears on the display, it does not always mean a serious failure—but it does indicate that the scooter has detected an issue that needs attention.
This guide explains the most common electric scooter error codes used on HALO KNIGHT scooters, including QS displays, Panda displays, Smart LCD central displays, and the T104 (2025) LED display. You will learn what each error code means, which issues require immediate attention, and when to contact official after-sales support.
This article is intended for basic diagnosis and understanding only and helps riders quickly identify common problems before further troubleshooting.
Why Electric Scooter Error Codes Appear
Electric scooter displays monitor key systems such as:
-
Battery voltage and BMS communication
-
Motor and Hall sensor status
-
Throttle and brake signals
-
Controller temperature and communication
When an abnormal signal is detected, the display shows an error code or warning icon to prevent unsafe riding and protect core components.
QS Display Error Codes Explained
The QS display uses decimal error codes to indicate system status.
| Error Code | Status Description |
|---|---|
| 0 | Normal status |
| 1 | Retain |
| 2 | Brake |
| 3 | The assistance sensor fault (riding symbol) (Not available) |
| 4 | 6 KM/H cruise |
| 5 | Real-time cruise |
| 6 | Battery undervoltage |
| 7 | Motor fault |
| 8 | Throttle fault |
| 9 | Controller fault |
| 10 | Communication receive error |
| 11 | Communication send error |
| 12 | BMS communication fault |
| 13 | Headlight fault |
📌 Note:
Some codes indicate system states (cruise / brake) rather than faults. This is normal behavior.
Panda Display Error Symbols Explained
The Panda display uses icon-based warnings instead of numeric error codes.
📸 Panda Display Error Icons Table
| Icon | Meaning |
|---|---|
 |
Electric brake fault (Normal during braking – indicates electronic brake is working) |
 |
Motor fault |
 |
Display fault |
 |
Controller fault |
📌 Important:
The exclamation icon appearing during braking is normal behavior and confirms that the electronic brake is active.
Smart LCD Central Display Error Codes
The Smart LCD central display (used on newer HALO KNIGHT models) shares a similar logic to the QS system and displays decimal error codes.
| Error Code | Status Description |
|---|---|
| 0 | Normal status |
| 1 | Reserved |
| 2 | Brake signal detected |
| 3 | Pedal assist sensor fault (not implemented) |
| 4 | 6 km/h cruise mode |
| 5 | Real-time cruise |
| 6 | Battery undervoltage |
| 7 | Motor fault |
| 8 | Throttle fault |
| 9 | Controller fault |
| 10 | Communication receive error |
| 11 | Communication send error |
| 12 | BMS communication fault |
| 13 | Headlight fault |
📌 This display is designed to provide clear, centralized fault information and improve troubleshooting efficiency.
T104 (2025) LED Display Error Codes
The T104 (2025) LED display uses an E-code system, specifically designed for dual-motor configurations.
| Error Code | Fault Description |
|---|---|
| E0 | Front motor 2 Hall sensor error |
| E1 | Rear motor 1 Hall sensor error |
| E2 | Throttle error |
| E3 | Controller 1 hardware fault |
| E4 | Brake error |
| E5 | Battery overvoltage error |
| E6 | Communication fault |
| E7 | Rear motor 1 phase loss |
| E8 | Controller 1 over-temperature warning |
| E9 | Rear motor 1 over-temperature |
| E10 | Battery undervoltage error |
| E16 | Controller 2 hardware fault |
| E17 | Front motor 2 phase loss |
| E20 | Motor 1 / Motor 2 stall warning |
📌 Warnings vs Errors:
Some codes (such as temperature or stall warnings) are protective alerts and may clear automatically after cooling down or restarting.
What Should You Do When an Error Code Appears?
Follow these basic steps:
-
Stop riding safely
-
Power off the scooter
-
Allow the scooter to cool down (if temperature-related)
-
Restart and check if the error clears
-
Avoid repeated riding if the error persists
⚠️ Do not disassemble electrical components yourself.
When to Contact HALO KNIGHT After-Sales Support
Please contact official support if:
-
The same error code appears repeatedly
-
Multiple error codes occur simultaneously
-
The scooter cannot power on or ride normally
📩 HALO KNIGHT After-Sales Support
Email: service@haloknights.com
Please include:
-
Scooter model
-
Display type
-
Error code or icon shown
-
Short video or photo if possible
Final Notes on Error Codes and Riding Safety
Electric scooter error codes are an essential part of modern safety and protection systems. Understanding what they mean helps riders respond calmly and correctly, avoiding unnecessary damage or unsafe riding behavior.
HALO KNIGHT designs its scooters with multi-layer system protection to ensure reliability, performance, and rider safety.
Share:
How to Measure Electric Scooter Battery Voltage – HALO KNIGHT Troubleshooting Guide
How to Use the 25km/h Speed Limiter Remote for Electric Scooters – HALO KNIGHT Guide
3 comments
Vervang het display, ik had ook E10. Na vervanging deed hij het weer
Pareil voyant rouge E2 et E4 fil écrasé
Ho una Bici Halo knight H03
Ha datto me errore E10
Cosa serve fare ?
La luce non funziona e la motore non partira con me
Grazie