1. Introduction
This manual provides essential information for the safe and efficient installation, operation, and maintenance of your KD21C Electric Bike Display and FSJMMYO3 / X759-AA001 Brushless Motor Controller. Please read this manual thoroughly before use to ensure optimal performance and longevity of your e-bike components.
2. Safety Information
- General Safety: Always wear appropriate safety gear when operating an e-bike. Ensure all connections are secure before riding.
- Electrical Safety: Installation should ideally be performed by a qualified technician. Disconnect the battery before performing any wiring or maintenance. Avoid exposing the controller and display to water or extreme moisture.
- Fire Risk: ⚠&#ufe0f; Please be aware of potential fire risks associated with electrical components. Ensure proper ventilation and avoid short circuits.
- Customized Product: This product is customized. Ensure it is compatible with your specific e-bike system (motor, battery, sensors) before installation. Contact the seller for compatibility verification if unsure.
3. Package Contents
Verify that all items are present and undamaged upon receipt:
- 1x Brushless Motor Controller (Model: FSJMMYO3 / X759-AA001)
- 1x KD21C Display Unit (KBY-Disp)
- 1x Wiring Harness (integrated with controller and display)
- 1x Pedal Assist Sensor (PAS) / Throttle (as pictured)
4. Setup and Installation
Installation of the controller and display requires careful attention to wiring. If you are not confident in your ability to perform the installation, please seek professional assistance.
4.1 Controller Mounting
- Mount the controller in a secure location on your e-bike, away from direct impact, water, and excessive heat.
- Ensure adequate ventilation around the controller for heat dissipation.
4.2 Display Mounting
- Mount the KD21C display (KBY-Disp) on your handlebar in a position that is easily visible and accessible for operation.
- Secure it firmly to prevent movement during riding.
4.3 Wiring Connections
The controller features various color-coded connectors. Match each connector to its corresponding component. Refer to the images for visual guidance. Common connections include:
- Battery: Connect the main power cables from the battery to the controller. Ensure correct polarity (red to positive, black to negative).
- Motor: Connect the motor phase wires (usually three thick wires) and Hall sensor wires (smaller connector) to the controller.
- Display: Connect the KD21C display cable to the designated display port on the controller.
- Throttle: Connect the throttle cable.
- Pedal Assist Sensor (PAS): Connect the PAS sensor cable.
- Brake Levers: Connect the brake lever cut-off switches (if applicable).
Important: Double-check all connections before powering on the system to prevent damage to components.
5. Operating Instructions
The KD21C display provides essential information and control over your e-bike's electric assist system.
5.1 Power On/Off
- To power on the system, press and hold the 'M' button on the display.
- To power off, press and hold the 'M' button again until the display turns off.
5.2 Assist Level Adjustment
- Use the '+' button to increase the pedal assist level.
- Use the '-' button to decrease the pedal assist level.
- The display will show the current assist level (e.g., 0-5). Level 0 typically means no assist.
5.3 Display Information
The display typically shows:
- Current Speed
- Battery Level Indicator
- Pedal Assist Level
- Odometer / Trip Distance (toggle with 'M' button)
5.4 Walk Assist Mode
- Some displays feature a walk assist mode. Typically, this is activated by holding down the '-' button. The motor will provide low-speed assistance for walking the bike. Release the button to exit.
6. Maintenance
- Cleaning: Wipe the display and controller with a soft, damp cloth. Do not use harsh chemicals or abrasive cleaners. Avoid spraying water directly onto the components.
- Connection Checks: Periodically inspect all wiring connections for tightness and signs of wear or corrosion. Secure any loose connections.
- Cable Management: Ensure all cables are neatly routed and secured to prevent snagging or damage during riding.
- Storage: When not in use for extended periods, store the e-bike in a dry, temperate environment.
7. Troubleshooting
If you encounter issues with your e-bike system, refer to the following common troubleshooting steps:
| Problem | Possible Cause | Solution |
|---|---|---|
| Display does not power on | Battery off or low charge Loose battery connection Loose display cable Controller issue | Ensure battery is on and charged Check battery connections Verify display cable is securely plugged into controller Consult a technician if controller is suspected |
| Motor not assisting | Assist level is 0 Loose motor phase/Hall sensor wires Brake levers engaged PAS sensor issue Throttle issue | Increase assist level Check all motor connections Ensure brake levers are fully released Check PAS sensor alignment and connection Check throttle connection and function |
| Inconsistent or no speed reading | Loose display connection Speed sensor (if external) issue | Check display cable connection Inspect speed sensor and magnet (if applicable) |
| Error code on display | Specific system fault | Refer to the display's specific error code list (if available) or contact seller/technician with the code. |
If the problem persists after attempting these solutions, please contact the seller or a qualified e-bike technician for further assistance.
8. Specifications
| Feature | Specification |
|---|---|
| Controller Model | FSJMMYO3 / X759-AA001 |
| Display Model | KD21C (KBY-Disp) |
| Type | Brushless Motor Controller |
| Battery Voltage | 36V / 48V |
| Current Limit | 15A |
| Rated Working Current | 6~25A (General range, specific model is 15A) |
| Maximum Working Current | 30mA |
| Off-state Leakage Current | <1μA |
| Working Temperature | -20℃ ~ 60℃ |
| Storage Temperature | -30℃ ~ 70℃ |
| High-concerned chemical | None |
| Origin | Mainland China |
9. User Tips
- Pre-Ride Check: Always perform a quick check of your e-bike's brakes, tire pressure, and battery level before each ride.
- Smooth Acceleration: Avoid sudden acceleration to prolong the life of your motor and controller.
- Battery Care: Do not fully discharge your e-bike battery. Charge it regularly, especially if storing the bike for an extended period.
- Environmental Awareness: Be mindful of your surroundings and local e-bike regulations.
10. Warranty and Support
For warranty claims, technical support, or any questions regarding your KD21C / FSJMMYO3 e-bike controller and display, please contact the seller directly. Keep your purchase records handy for faster service.
