Pixhawk BAD ACCEL HEALTH APM 3.2 - collecting data

A few users, myself included, appear to be having issues calibrating accels and/or arming when using APM 3.2 on a Pixhawk.  I see posts here and there, but thought it may be best if those having the issue could all 'check in' to one post so that the developers can see how widespread the issue is and gather data.

My Pixhawk will arm occasionally, and will even fly successfully.  Occasionally however it will not arm and I will receive the pre-arm error "Accels not healthy".  A few days ago I was able to arm and fly thorugh one lipo, then after landing and swapping batteries I could not arm due to this reason.  I have attached the logs from the successful flight, as well as the failed pre-arm logs, to this post.

As you can see from these images there is something amiss with IMU2.  This is a snippit from the good flight, showing values for AccX on IMU1 and IMU2:

3691166950?profile=original

and here are the same values on the second attempt, pre-arm.

3691167027?profile=original

In the 3.2 release thread a few users had mentioned the issue and Randy advised to set the log_bitmask to "131070" so that it will log everything including the pre-arm checks.  I encourage others having the issue to do the same and share the logs and experiences here so that we can find out what is going on here - is there a bad batch of Pixhawks in the wild that only now show the hardware errors due to something new in 3.2, or is there an issue in the APM software?

goodlog.bin

badlog.bin

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            • Could you post a log.

              I tried to find logs from when I was still on 3.1.5. but i deleted most of them and the ones I have aren´t faulty.

          • I was speculating that one of my accelerometers soldering points is disconnected form the board by the temperature change. And once the whole FC is cooled down it reconnects. i.e. bad soldering.
            There is one other guy here in Germany having the same issue.
            And after some minutes outside it just goes away.

            Would be interesting what happens if someone just took one of a board for testing ;)

            • That's definitely a possibility - but did you have this problem prior to 3.2?

              I guess something we should test is going back to 3.1.5 and testing in the same conditions, and then comparing the logs to see if IMU2 is exhibiting the same behavior.

              I'll try it this evening if I get the time.

    • Do you have the log that shows the constant values on IMU2?  That sounds exactly like what I am experiencing.

      • It´s in the "Bad.BIN" I posted above.

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