mRo x2.1 Rev 2 - No arming and Bad Ahrs message - How to check IMU health?

How can the IMU health checked ?

I mount a mRo x2.1 Rev 2 on a plane with Arduplane 3.8.4 .

  • with Arming Check set to 1 I’m unable to arm the motors
  • sometimes on Mission Planner HUD with the plane on ground, the “bad Ahrs” message appears on Mission Planner HUD
  • In Mission Planner the EKF window shows all elements in OFF state

If I set Arming check to 0 , the plane flies without problem, the Bad Ahrs message do not appears anymore and the EKF window shows all elements in ON state with all bars showing the grren bar at minimum.

Mission Planner Auto Analysis gave:
Test: IMU Mismatch = GOOD - (Mismatch: 0.33, WARN: 0.75, FAIL: 1.50)

Have you solved this? I have disabled compass and I have a good GPS lock and still I get bad AHRS. I see no remedy. I hate the idea of disabling all arming checks to circumvent this. It seems this is still a thorny area.