CUAV V6X enters continuous reboot loop after any reboot (soft or hard)

Hi everyone,

I’m facing a strange issue with my CUAV V6X flight controller.

Hardware

  • Flight Controller: CUAV V6X
  • Firmware tested:
    • ArduPilot Copter 4.6.3 (Pixhawk 6X target)
    • PX4 (latest stable available in QGroundControl)
  • GCS: Mission Planner / QGroundControl
  • RC: Skydroid H12

Problem

Initially, everything was working normally. While connected through the H12 telemetry, I issued a reboot command (soft reboot). After that, the flight controller entered a continuous reboot loop.

The symptoms are:

  • FMU LED flashes green briefly.
  • The startup melody begins but is interrupted.
  • The controller reboots every 3–5 seconds.
  • USB repeatedly disconnects and reconnects.
  • The board never completes the boot sequence.

The power LED remains on, so it does not appear that the board is losing power completely.

What I have tried

  • Reflashed ArduPilot 4.6.3 (Pixhawk 6X) successfully.
  • Reflashed PX4.
  • Removed the microSD card.
  • Disconnected peripherals.
  • Connected using USB only.

After reflashing, the board boots normally and I can:

  • Connect to Mission Planner/QGroundControl.
  • Calibrate the accelerometer.
  • Change parameters.
  • Configure the board without any issues.

However, the moment the FC performs any reboot (either a software reboot or a normal power cycle), it immediately returns to the same endless reboot loop.

This happens regardless of the parameters I change. It is not tied to one specific parameter—the board functions normally until it is rebooted.

Questions

  • Has anyone seen this behavior before on a CUAV V6X?
  • Could this indicate corrupted parameter storage, bootloader corruption, or a hardware issue?
  • Is there a way to completely erase all persistent storage (parameters/FRAM/flash) and recover the board?

Any suggestions would be greatly appreciated. Thank you.