My Quadcopter has problem with RTL, circle

Hardware Multirotors
1

Hi APM Forum!.

I´m new user of this forum and i builded a quadcopter with APM 2.8. GPS 6 Ublox, telemmetry 433Mhz.
I have 5 flight modes programmed (Stabilizate, RTL,Circle, Alt Hold, Land) and after of arm it when turn on the switch for RTL in my PC appear RTL with background Red colour and my quadcopter only stay in alt position and the controls that can be modify is roll . I wait 5 seconds, 10 seconds, 20 seconds…

Is it possible that the problem is that the blue LED of GPS is blinking ? …
My ardupilot is this
http://www.banggood.com/APM-Flight-Controller-Set-APM-2_8-6MH-GPS-OSD-Radio-Telemetry-etc-p-960341.html

also with circle mode, the same, alt position but quadcopter moves up

Land ok!, Stabilizate ok. loiter (geo fence error, GPS HDOP high)

thank you!!!

2

RTL, and I “think” circle both require a good solid GPS lock.
If you have a GPS error showing, you don’t have that which will be your problem but log files of the event would be very useful.