User Manual for E-bike Display

1. Product Name and Model

Intelligent LCD display for e-bike; model: YL81C.

2. Specifications

• 36V/48V power supply
• Rated working current 15mA
• Maximum working current 30mA
• Leakage current at power-off <1uA
• Working current at the supply controller end 50mA
• Working temperature -20~60℃
• Storage temperature -30~70℃

3. Appearance and Dimensions

A close-up image shows the front of the YL81C e-bike display mounted on handlebars. The display shows speed '25 km/h', assist level '3' (PAS), and time '96:42.8'.

A diagram shows the top view of the display unit with dimensions. The mounting clamp has a diameter of 22.2mm and a height of 48.5mm.

A diagram shows the side view of the display unit with dimensions. The overall width is 70.0mm and the height is 37.0mm.

4. Function Overview and Functional Area Layout

4.1 Function Overview

The YL81C display provides a variety of functions to meet riding needs, including:

• Battery level indicator ?
• Assist level adjustment and indication
• Headlight indicator ?
• Speed indicator (real-time speed, maximum speed (MAXS), and average speed (AVG))
• Distance indicator (ODO and trip distance (Trip))
• Error code indicator ⚠️
• Bluetooth connection indicator (reserved) ?
• Parameter setting function

4.2 Functional Area Layout

Diagram illustrating the layout of the YL81C display interface. Key areas include:

• Battery level indicator (represented by segments)
• Speed indicator (showing speed in km/h or MPH)
• Assist level indicator (PAS level)
• Maximum speed indicator (MAXS)
• Trip distance indicator (TRIP)
• ODO indicator (ODO)
• Bluetooth indicator ?
• Headlight indicator ?
• Speed unit display (Metric: km/h, Imperial: MPH)
• Average speed indicator (AVG)
• Distance/speed unit display (Metric: km, km/h; Imperial: mile, mph)

4.3 Button Definitions

The display has three buttons:

• On/off button ?
• Plus button ➕
• Minus button ➖

5. General Operation

5.1 Power On/Off

Press and hold the ? button to turn the display and controller power on. Press and hold the ? button again to power off the e-bike. When powered off, the display uses less than 1uA leakage current. The display automatically powers off after 10 minutes of inactivity.

5.2 Display Interface

After powering on, the display shows real-time speed and trip distance by default. Pressing the ? button cycles through trip distance, ODO, maximum speed, and average speed. The trip distance resets automatically after reaching 9999.9 km.

Diagram showing the cycling of display information: Trip Distance -> ODO -> Average Speed -> Maximum Speed.

5.3 Push Assistance

Press and hold the ➖ button to enable push assistance mode. The e-bike will move at a constant speed of 6km/h, indicated by 'P'. Releasing the ➖ button stops power output and returns to the previous state.

Shows the display indicating 'PAS P'.

5.4 Headlight On/Off

Press and hold the ➕ button to turn on headlights and dim the display backlight. Press and hold the ➕ button again to turn off headlights and restore backlight brightness.

Shows the display with a headlight icon illuminated.

5.5 Assist Level Selection

Press the ➕ or ➖ buttons to switch the e-bike assist level, changing motor output power. Available levels include 0-3, 1-3, 0-5, 1-5, 0-7, 1-7, 0-9, and 1-9.

Shows the display indicating PAS level '3'.

5.6 Battery Level Indicator

The battery is indicated by five segments. Full charge shows all five segments. Low battery is indicated by the battery outline flashing.

Depicts battery levels from full (5 segments) down to low (1 segment) and an undervoltage flashing state.

5.7 Error Code Indicator

When a fault occurs, an error code (format E0**) is displayed. Detailed definitions are in Schedule 1.

Shows an example error code 'E002'.

If an error code appears, troubleshoot promptly to ensure normal operation.

6. General Setting

Parameters can only be set when the e-bike is stopped (speed is 0).

6.1 Trip Distance Reset

Press and hold the ➖ and ➕ buttons simultaneously for over 2 seconds to reset the trip distance.

6.2 Factory Reset

dEF refers to factory reset. 'dEF-n' means not to restore factory settings, and 'dEF-y' means to restore them. Press and hold the ➖ and ➕ buttons simultaneously for over 2 seconds to enter the factory reset interface. Press the ➖ button to select a parameter.

Shows the display indicating 'dEF-n'.

7. Custom Setting

Parameters can only be set when the e-bike is stopped (speed is 0).

Steps for Custom Setting:

1. Press and hold the ➖ and ➕ buttons simultaneously for over 2 seconds to enter the custom setting options interface.
2. Press the ➕ button to switch to the general setting options interface, and press the ? button to enter the parameter modification interface.
3. Press the ➕/➖ buttons for parameter selection.
4. Press the ? button to save the parameter and return to the custom setting options interface.
5. Press and hold the ? button to save the parameter and exit the custom setting interface.

7.1 Rated Voltage Setting

P1 is the rated voltage setting. Options: 36V, 48V. Press the ? button to enter modification. Use ➕/➖ for selection. Press ? to save.

Shows 'P1' and '36 V'.

7.2 Wheel Diameter Setting

P2 is the wheel diameter setting. Range: 8-32 inches. Press ? to enter modification. Use ➕/➖ for selection. Press ? to save.

Shows 'P2' and '20 in'.

7.3 Speed Limit Setting

P3 is the speed limit setting. Range: 10~40km/h. Press ? to enter modification. Use ➕/➖ for selection. Press ? to save.

Shows 'P3' and '25 Km/h'.

7.4 Metric/Imperial System Setting

P4 is the system setting. '00' for metric, '01' for imperial. Press ? to enter modification. Use ➕/➖ for selection. Press ? to save.

Shows 'P4' with '00' (Metric) and '01' (Imperial) indicators.

7.5 Speed Sensor Setting

P5 is the speed sensor setting, based on magnetic heads on wheels. Range: 1-63. Press ? to enter modification. Use ➕/➖ for selection. Press ? to save.

Shows 'P5' and '01'.

7.6 Current Limit Setting

P6 is the current limit setting. Range: 1-25A. Press ? to enter modification. Use ➕/➖ for selection. Press ? to save.

Shows 'P6' and '13'.

7.7 Assistance Sensor Setting

P7 is the assistance sensor setting, based on magnetic disk magnets. Range: 5, 6, 7, 8, 9, 10, 12. Press ? to enter modification. Use ➕/➖ for selection. Press ? to save.

Shows 'P7' and '12'.

7.8 Power-on Password Setting

P8 is the power-on password setting. 'PSd-Y' requires a password, 'PSd-N' does not (default). Press ? to enter modification. Use ➕/➖ for selection.

If PSd-N is selected, press ? to return to custom settings.

If PSd-Y is selected, press ? to enter password interface. To exit without changing, press and hold ?. To change password, use ? for cursor and ➕/➖ for figure selection, then press ? to return.

Shows 'P8' and 'PSd-n'.

8. Quality Commitments and Warranty Scope

8.1 Warranty Information

The Company provides limited warranty for product quality faults under normal use. The warranty period is 12 months from delivery.

8.2 Non-Warranty Scope

• Enclosure opened
• Connector damaged
• Enclosure scratched or damaged after delivery
• Outgoing line scratched or broken
• Faults or damage from force majeure (fires, earthquakes, natural disasters)
• Warranty period expired

9. Outgoing Line Connection Diagram

9.1 Wiring Sequence of Standard Connector

Diagrams show the connecting terminal to the controller, the leading-out terminal of the display, and a connecting terminal. The standard wiring sequence is detailed in the table:

Note: Some products use waterproof connectors where internal wire colors are not visible.

10. Considerations

• Use safely; do not plug or unplug the display when powered on.
• Avoid bumping the display.
• Do not alter background parameter settings arbitrarily, as it may affect normal riding.
• If the display malfunctions, seek repair promptly.
• Due to product upgrades, displayed content or functions may differ from the manual based on the actual model.

Schedule 1: Error Code Definitions

Error Codes for Protocols YL-01 and YL-02:

Error Codes for Protocols YL-05, KDS and YL-J:

Email for support: service@engwe-bikes.com