Find the right instructions for your bike
- Identify the model and generation. Use Aventon’s manual directory. Choose your model family, then the exact generation. If you are unsure, use the manufacturer’s serial-number identification guide rather than guessing from the frame shape.
- Match the complete code and its meaning. Photograph the display, then compare it with the error section of that exact model’s manual. Keep any letter prefix in your record.
- Choose the matching help section. Aventon’s error-code directory separates hub-drive and mid-drive guidance. The hub-drive index also marks entries that are specifically for bikes with an ACU/ECU (Aventon Control Unit). If you cannot establish which instructions apply, send the model, serial number and display photo to Aventon before trying a procedure.
For a concrete check, the official Pace 500.3 manual page links a PDF whose error table is on printed page 26 (PDF page 27). It lists 25 for brake-switch trouble or braking during startup, and 30 for communication trouble. It recommends stopping operation and contacting Aventon when a code appears. Use those meanings for that manual; it does not establish that every help-center code applies to the Pace.
Three examples from Aventon’s hub-drive guidance
| Code | What Aventon’s linked article reports | Useful detail to record |
|---|---|---|
| E25 | Brake-lever motor-cutoff sensing | Whether a brake lever was held during startup |
| E30 | Communication between controller and display | Recent cable work, impact or visible connector damage |
| E31 — C.A.N. | Battery communication with the display | Whether the battery or display was changed |
Use the full official hub-drive index for other hub codes and their individual scopes. For a mid-drive bike, return to the system selector above.
E25: was a brake held when you switched on?
Aventon identifies holding a brake during startup as one possible trigger. Include that detail in your support request. For a persistent E25, use the matching brake-sensor guidance with Aventon or a qualified service shop.
Aventon’s E25 diagnostic flowchart includes sensor-disconnection steps to isolate a fault. Leave that diagnostic work to service guidance for your exact bike. Do not ride with brake-cutoff sensors disconnected to make the code disappear.
E30: a communication fault is not a display diagnosis
The official article points to the controller/display connection and includes cables and connectors in its checks. Note any visible damage or recent work without opening components. Ask which powered-off inspection applies to your bike before disconnecting anything.
Aventon lists the display, controller and wiring harness as possible replacement candidates if checks do not resolve the fault. Give support the observations before buying a display.
E31: battery communication on C.A.N. bikes
The hub-drive article names E31 as a C.A.N. battery-communication failure. Its explanation concerns the battery/display connection and lists several possible components, not just the battery. Ask support to identify the applicable checks before ordering a pack.
If the battery or charger is damaged, use our battery-problem and safety triage before troubleshooting a communication message.
Prepare one useful support request
Copy this into a request to Aventon support or your service shop, filling in only what you know:
- Bike: exact model, generation and serial number; market of purchase.
- Display: full code and a photo; display model or firmware if known.
- Timing: startup, braking, assist or another observed circumstance.
- Recent changes: impact, wet conditions, transport, cable work or replacement parts.
- Source and checks: manual title/page, help-page link, steps actually performed and codes before/after.
- Question: “Which owner checks apply to this configuration, and which work needs your service partner?”
If no code appears, describe the symptom rather than choosing a code that sounds close. Start with the no-power section of the battery guide linked above.
The examples use Aventon’s U.S.-English help pages and the linked Pace 500.3 manual. E31’s C.A.N. label comes from its own help article; the Pace manual example establishes only codes 25 and 30.