Accelerometer calibration always fail

Hi All,

I am trying to calibrate my accelerometer for Pixhawk 2.4.8 but it always failed after asking to put it level, right, left, nose up , nose down then level again.
calibration failed

I plotted the acc for all axises and I can see that one az, az2 and ay2 always have large values.

are the IMUs damaged?

On the graphs they do not look damaged.

If you to not level with enough precision, and do not stay perfectly sill while pressing the button, it will give you the error that you are getting.

If you are doing as listed above the last step is wrong.
The level backside is missing.

I agree.
when it say back. I thought back to original state not backside.

I did the calibration and it succeed. but the values of az, az2 are still in range of 1000, is this normal ?