Pre-Arm Fail - GPS Blending Unhealthy


We have been using GPS Blending for 10 or so flights without issue on Arducopter 3.5.2. During our last session flying we got a pre-arm fail of “GPS Blending Unhealthy” (I dont have a log as we dont log while disarmed - although we can turn on and try again) I had to disable the blending function (GPS_AUTO_SWITCH) back from 2 to 1 (Use Best) to fly.

What we would like to learn about initially is what are the causes that would trigger this pre-arm fail.



For personal stats, do you use the same gps?

Yes - 2 x CUAV Mini with Ublox NEO-M8N. They are on the axis line but 520mm
apart. I have set up with offsets within the parameters

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I also have “GPS Blending Unhealthy” on a PH2 with HERE+ and Ublox M8N
No clue why. 17 cm apart and measurements input into the formula…

Hi Jimmy, I’m sorry I can not help - we never switched back to blending but have had success with “Use Best” and so have stuck with it at this time.

Now GPS 1 is “failing configuration checks” This is a copter that is identical, but never had the “blending” issue. There are 19 Sats so I’m stumped. I have 6 identical Vulcan Hexacopters used for agriculture.