Charger displays E020; app shows OCPP or backend communication error; smart charging features disabled.

Note: Backend communication faults do not usually affect basic charging but may affect billing and remote control.

• Check internet access: Ensure the home router has internet connectivity and that outbound ports required by EVBox/OCPP are not blocked.
• Verify OCPP settings: In the installer portal, confirm the correct server URL, port, and credentials are configured.
• Cellular models: For units with built‑in modems, check SIM validity and signal strength via the EVBox portal.
• Reboot charger and router: Power cycle both the EVBox and the network router.
• If E020 persists: Contact EVBox support to verify backend status and, if needed, update firmware or replace the communication module.