S866 LCD · Brake switch
25 S866 LCD error code 25
Brake abnormality
Widely published – may differ by model/firmware
Note
Common error table of generic Chinese LCD displays (JN-type controllers). The paired controller defines the actual meaning.
Possible causes
General, component-based causes – not a manufacturer-specific statement.
- Brake lever does not fully return
- Brake switch/magnet misaligned or faulty
- Brake switch cable damaged
Safe test steps
- Lever return, magnet/sensor position.
- Unplug switches one at a time for diagnosis (reconnect afterwards!).
Workshop reference values
- Brake switches are normally-open, normally-closed or Hall type – measure per the manufacturer diagram.
Repair approach
- Adjust or replace the brake lever/switch.
Tools needed
- Digital multimeter (CAT III, fused inputs)
- Basic hand tools, insulated screwdrivers
Safety
- Never permanently disable the brake motor cut-off.
This information does not replace manufacturer service documentation. Work on batteries and high-voltage parts only with the appropriate expertise.