Knowledge base
Communication
Possible causes
- Harness/connector fault (break at handlebar, corrosion)
- Incompatible component/firmware
- Component supply fault
Safe test steps
- Unplug connectors, check pins and corrosion.
- Compatibility (protocol UART/CAN, firmware).
Workshop reference values
- Voltages on communication lines depend on the protocol; measure only with the manufacturer pinout.
Repair approach
- Repair harness/connector; use compatible component/firmware.
Tools needed
- Digital multimeter (CAT III, fused inputs)
- Contact cleaner, dielectric grease
- Manufacturer dealer diagnostic tool/software (if available)
Safety
- Power down (remove the battery) before unplugging connectors. Never apply pack voltage to data wires.
Related verified fault codes
| Code | Meaning | Component | Reliability |
|---|---|---|---|
| Bosch 414 | Connection problem with the control unit | Communication | Per manufacturer documentation |
| Bosch 422 | Connection problem with the drive unit | Communication | Per manufacturer documentation |
| Bosch 423 | Connection problem with the battery | Communication | Per manufacturer documentation |
| Bosch 424 | Communication error between components | Communication | Per manufacturer documentation |
| Bosch 595 | Communication error | Communication | Per manufacturer documentation |
| Bosch 596 | Communication error | Communication | Per manufacturer documentation |
| Shimano STEPS E020 | Communication error between battery and drive unit | Communication | Per manufacturer documentation |
| Bafang 30 | Communication fault | Communication | Per manufacturer documentation |
| SW900 LCD 30 | Communication abnormality | Communication | Widely published – may differ by model/firmware |
| S866 LCD 30 | Communication abnormality | Communication | Widely published – may differ by model/firmware |
| Xiaomi 10 | Communication error between dashboard and control board | Communication | Widely published – may differ by model/firmware |
| Segway-Ninebot 10 | Communication error between dashboard and control board | Communication | Widely published – may differ by model/firmware |