The two GPS receivers cannot be blended

What ArduPilot says:

• GPS blending unhealthy

GPS_AUTO_SWITCH is 2: ArduPilot mixes the positions of two receivers into one, weighting each by the accuracy it reports. That needs both to have a fix, to report accuracy, and to deliver data in step: their latest messages no more than two update intervals apart. Every failed attempt adds 10 to a counter and every success takes 1 off; from 50 up, blending counts as unhealthy and arming is refused.

What to do, most likely first

1. One of the two receivers has no fix yet, or is not connected.

   CheckLook at the fix and satellite count of GPS 1 and GPS 2 separately.

   FixWait for both, or repair the missing one.

2. One receiver does not report the accuracy figures that blending weighs by (many NMEA receivers do not).

   CheckGPS_BLEND_MASK chooses which figures are used: horizontal position, vertical position, speed.

   FixBlend only two receivers of a kind that both report accuracy; otherwise set GPS_AUTO_SWITCH to 1, which uses whichever receiver has the better fix.

3. One receiver updates late or irregularly.

   Check“GPS 2: not healthy” (or 1) appears as well.

   FixSolve that message first.

Parameters to look at