Reading Your Logs
A practical guide to interpreting your Zero's data: what to look for, warning signs, and when to take action.
TL;DR
Focus on: cell balance delta (B <50mV is healthy), temperature trends, SOC consistency, and any error codes. Most logs show normal operation — you're looking for outliers and patterns that change over time.
1. Battery Health Check
The most important indicator of battery health is cell balance. Look at theB field in BMS logs:
Cells are well matched and balanced
Some imbalance — may improve with full charge
Significant imbalance — possible weak cell
What to do:
- •If B >50mV consistently, try a full 100% charge to allow balancing
- •Track B over multiple charges — trend matters more than single reading
- •B >150mV consistently may warrant dealer inspection
2. Temperature Patterns
Unusual temperature readings can indicate problems. Compare temperatures against ambient and look for patterns:
Normal — motors warm up during use and reach thermal equilibrium
May indicate cooling issue — check airflow around controller
Unusual — battery shouldn't heat significantly at rest
3. SOC Consistency
State of Charge should correlate with voltage and behave predictably:
Normal Behavior
- • SOC drops smoothly during rides
- • SOC rises steadily during charging
- • 100% SOC corresponds to ~116V pack voltage
- • Small SOC increases from regen
Warning Signs
- • Sudden large SOC drops (10%+ instantly)
- • SOC doesn't match expected voltage
- • SOC "jumps" when bike restarts
- • Full charge shows <100% or voltage low
4. Error Codes & Events
Logs record error codes when the bike detects issues. Common categories:
| Category | Examples | Action |
|---|---|---|
| Warnings | Low SOC, High Temp | Informational, usually self-resolving |
| Thermal | Motor/Ctrl Overtemp | Let bike cool, check cooling |
| Battery | Cell voltage errors | May need dealer inspection |
| Communication | CAN errors, module offline | Check connections, may be intermittent |
For detailed error code meanings, see the ZeroManual Error Codes reference.
5. Riding Pattern Insights
BattAmps >80A sustained = aggressive riding. Expected to increase temperatures and reduce range per charge.
Lots of negative amp periods = hilly terrain or sport mode with aggressive regen. Good for battery recovery.
Compare Wh/km across rides. Highway is typically 80-120 Wh/km, city 50-80 Wh/km. Changes may indicate issues.
Note if full charges take longer than expected. Significantly longer times may indicate cell degradation.
Quick Health Checklist
After Every Few Rides
- □Cell balance B <50mV
- □No new error codes
- □Temps stayed in normal range
Monthly Review
- □SOC tracking accurately
- □Charge times consistent
- □No recurring error patterns
- □Efficiency (Wh/km) stable
When to Contact a Dealer
- Persistent cell imbalance (B >150mV) that doesn't improve with full charges
- Recurring error codes, especially battery-related
- Significant range loss (>20%) not explained by temperature or riding style
- SOC readings that don't match voltage or behave erratically
- Any safety-related warnings or reduced power that persists
For troubleshooting steps, see the ZeroManual Troubleshooting guide.
Ready to Analyze Your Logs?
Upload your Zero's log files and put this knowledge to use.
This guide is for educational purposes. Always consult with an authorized Zero dealer for official diagnosis and warranty-related concerns.