Firmware update failed

Overview

Firmware update stuck or aircraft not recognised. Safe recovery for DJI and FPV.

DJI Fly/Pilot, DJI Assistant 2, Betaflight, INAV, ArduPilot.

Symptoms

Typical "Firmware update failed" signs in flight, app or OSD:

• Update stuck at percentage (e.g. 45%)
• PC/app aircraft not recognised
• Bricked — won't boot or only beeps
• RC linked but aircraft not
• Rollback impossible — error code
• Log firmware versions: aircraft, RC, app.

Common causes

Before replacing parts, rule out software, mechanical and environmental causes:

• Battery <50% during update
• Charge-only USB — no data transfer
• Sleep mode / phone screen locked
• Network drop during cloud download
• Incompatible firmware package

Tools needed

Prepare before diagnostics — saves time in the field:

• Data USB
• Full battery
• Backup config (BF .bbl / DJI log)

Step-by-step fix

Work safely: battery off when working on ESC/motors; props removed; after repair — VLOS test flight.

• 1. Full battery (>80%) and data-capable USB direct to aircraft.
• 2. DJI Assistant 2 (Consumer/Enterprise) — recovery mode per model.
• 3. Do not close app/PC until update completes — stable Wi-Fi.
• 4. FPV: DFU mode — Betaflight/INAV flash with correct target.
• 5. If bricked — DJI support with logs; avoid custom firmware without experience.

Additional diagnostics

Log firmware versions: aircraft, RC, app.

ATTI mode — GPS vs sensor health.

Vision cal — in well-lit room.

When to contact service

If any of the following apply — do not fly and contact authorised service:

• Firmware update stuck >30 min — DJI support with logs.
• Aircraft not recognised by PC — recovery mode.
• Vision sensor error after cleaning — service.

Prevention

Prevention reduces failure risk and supports EASA Open / VLOS compliance:

• Config backup before update
• Stable Wi-Fi
• Do not charge during update

Frequently asked questions

Is it safe to fly with "Firmware update failed"?

No if the fault affects navigation, power, ESC or link. Fix on the ground first, then conduct a VLOS test flight in open area.

How long does diagnosis take?

Most “Firmware update failed” cases — 15–45 min on the ground. Complex ones (firmware, hardware) may need 1–2 h and service.

Must I register repair with the NAA?

No mandatory repair registration, but a maintenance log is recommended for commercial operations.