GPS Status = 0 but showing GPS Fix

Hi Everyone,

I’m new around here having recently switched from a different flight controller to a Pixhawk running APM. Really excited about all of the features this has over my last setup so keen to make the most of it.

I have a 3DR Pixhawk (not sure of the hardware version) and I have APM Copter 3.2.1 running on it. With the Pixhawk I bought a uBlox Neo-M8N gps and compass. I seem to be having some trouble with the GPS.

I’ve connected the GPS and I2C wires and when I connect USB to the Pixhawk it boots up nicely and, the first time I did it, immediately complained about mag uncalibrated etc. That’s obviously fine, so I completed the compass calibration and the main Pixhawk LED switched from an amber double flash to a slower, single blue flash. It seemed quite happy with the calibration and the relevance being that it is clearly talking to the magnetometer fine.

After a couple of minutes a blue light started flashing on the GPS unit which seemed reasonable. It took a minute or two to get a GPS fix but then got one. Everything up to this point seems fine.

The problem now is that the Mission Planner’s PFD shows “No GPS”. I then looked in the status tab and find “gpsstatus” is showing as 0. I quick google lead me to a similar report and informed me that it should be 1 is a gps has been detected.

My best guess at the moment is that it might be “building it’s almanac”. I say that very loosely as it’s not a term I’m familiar with but gather that GPS receivers have to do this sometimes, more frequently when they are new. I also read that it can take several hours. That’s fine, if that’s what it’s doing, but I might have thought the gpsstatus would show as 1? Unless the unit is not communicating because it’s busy sorting itself out.

I also tried the MAVSerial passthrough but my version of u-Centre is newer than the tutorial and doesn’t give me the same TCP option, so I can try a “direct” test of the GPS receiver.

Has anyone else had a similar experience? I’m happy to wait if it needs to sort it’s almanac out but just a bit in the dark as I don’t know whether that’s what it’s doing.

Oh, I also tried it running from flight battery power instead of USB in case the voltage was important. “hwvoltage” reads about 4.9V on USB but 5.23V on battery power. Didn’t seem to make a difference.

There’s also no power light I can see on the GPS unit but the blue fix light is flashing away quite happily.

Anyway, I think that’s about it. If anyone can help I’d very grateful!

Thanks very much!

Just left it on all day whilst at work, still showing gpsstatus = 0 and no fix.

Any ideas anyone?


Did you ever get a solution to this?

I am also having the same problem problem for both APM and for Pixhawk.

I was able to configure U-blox using the mavlink passthrough on a pixhawk:
Mission Planner on flight data window:
hit ctrl-F
push once the green bar/button that says “MAVSerial Pass” it doesn’t look like it does anything but if you hit it twice mission planner just stops working.

Then to:
U-Center 8.18 on Windows 8.1:
Receiver->Port->network connection enter: tcp://localhost:500
Tools -> GNSS configuration

I had it repeat each command 3times and it seemed to work.

However, mission planner still shows “No GPS”. Even when pixhawk is showing a blinking green (ie 3D lock). or the APM is showing steady blue. I have two setups and both do not work.

The gps I am using is the hobby-king clone Neo-6M-0-001 ROM 7.03 (45969)

I had the same problem. The only solution I’ve found so far is downgrade to 3.1.5 which seems to work.