So here's the issue:
My APM2.0 always has the 3DFix light go solid within a couple minutes, but quite frequently Mission Planner will display "No GPS" (and of course hdop:0 and sats:0) when connected via 3DR radios. I can get the GPS to register by disconnecting Mission Planner, pressing the reset button on the APM2, and then reconnecting Mission Planner. The GPS will keep its 3D Fix during the AMP2 reset. Sometimes I need to do this more than once before "No GPS" will turn into "No Fix" or "3D Fix" on Mission Planner. Everything seems to work fine when connected via USB instead of radio. All other sensors/telemetry work fine. I am using Mission Planner 1.1.85 and ArduPlane 2.34, which are the current versions.
Does anyone know why Mission Planner fails to detect/read the GPS on my APM2.0?
Cody: Actually, that guide is right in the manual.
That's embarassing. The frequency of updates on this site is awesome!
I read the guide when it was a pdf linked-up in a thread somewhere.
I finally solved my problem by powering the APM from my receiver to the input rail, bridging positive and negative over to the output rail AND using the APM power module, all with JP1 connected. It's the only scenario that allows my GPS to work.