Crazy radio

I’ve got a bunch of 3DR radio’s and never have had a problem connecting with mission planner unit now. It’s attached to a Pixhawk. These are the new radios with the case. I have one Pixhawk in a quad that won’t connect. It will connect via usb, but just times out on the radio. Other radio’s connected to other Pixhawks connect fine. Even swapping the working multirotor’s radio to the quad in question fails to connect. It’s a new Pixhawk that’s having the issue so it doesn’t seem to be the radio at all. Anything on the Pixhawk that would cause Mavlink not to connect? I heard about faulty micro sd cards, but swapped that out with a working unit with the same results. Bad Pixhawk?

Please check you have the same NetID in the radios, with mission planner or apm planner, enter initial setup, optional hardware, 3DR Radio

NetID is 25 on all of the radio’s. All the radios work, just not on this one Pixhawk. All the other Pixhawk autopilot work with all the radio’s. None of the radio’s work with the Pixhawk I have on my quad. Maybe a bad telemetry port? I’ll try reflashing the Pixhawk.

I can’t believe I swapped all those radio’s and Pixhawk combination without noticing if the power light on the radio is even on! It’s not on that one Pixhawk. I’m guessing is probably the connector on the board itself as I’d tried other cables as well. Sometimes the answer is staring you in the face. Sad, I just got this one.

Assuming you have the telemetry radio connected to TELEM 1 port, and you are not getting any light in the telemetry radio, please try with the TELEM 2 port

BTW, thanks for all the help! I thought there was some reason not to use telem port 2? Anyhow, port 2 lights up and the radio connects! Is there any issue using port 2?

No, the problem will be if you want to use both of the telemetry ports at the same time, for example to connect a minimOSD.

Please send an email to for further help with the TELEM 1 issue.