Knowledge base
Voltage
Possible causes
- Low state of charge / heavy sag under load
- Over-voltage (wrong charger, unsuitable battery)
- Faulty voltage sensing in the controller
Safe test steps
- Pack voltage at rest and under load vs. the controller voltage class.
- Charger output voltage per label (S × 4.20 V Li-ion).
Workshop reference values
- Typical controller low-voltage cutoff: approx. 3.0–3.15 V/cell (~30–31.5 V on 36 V) – controller-specific.
Repair approach
- Charge the battery; if it still drops under load: battery diagnosis.
- Replace a battery/charger of the wrong voltage with a matching one.
Tools needed
- Digital multimeter (CAT III, fused inputs)
- Fused load tester
Safety
- Never use a battery or charger of a different voltage with the system.
Related verified fault codes
| Code | Meaning | Component | Reliability |
|---|---|---|---|
| Bosch 610 | Battery voltage fault | Voltage | Per manufacturer documentation |
| Bafang 07 | Over-voltage protection | Voltage | Per manufacturer documentation |
| Bafang 41 | Total battery voltage too high | Voltage | Per manufacturer documentation |
| Bafang 42 | Total battery voltage too low | Voltage | Per manufacturer documentation |
| Xiaomi 24 | Supply voltage abnormal | Voltage | Widely published – may differ by model/firmware |
| Segway-Ninebot 24 | Supply voltage abnormal | Voltage | Widely published – may differ by model/firmware |