PX4 stopped working after testing retractable gear

PX4 (buzzer & afety switch only) & X8R (on rc in) working properly, on a 3S normally charged battery, controlled by a Taranis. All new and set up!
Tested 1 SR 15KG High-torque Digital Servoless Retractable system (SR)
(funtobuyonline.com/15kg-high … ystem.html)
connected to ch8 on X8R, everything ok. Switched off, unplugged 1 SR, plugged the second SR, switched all ON, everything OK, command switch - goes down! I hit the switch to retract 2 SR…everything stops working.

Now, connected on the same battery or only via USB to PC, the PX4 Pixhawk makes a sound like described at "Firmware update found, restart while holding the safety button"
and the FMU (left side) lights light solid (not bright)

I hope you supplied separate 5 volt supply to servo out buss of Pixhawk. :open_mouth:

If not, you might have overloaded the Pixhawks 5 volt power supply which sometimes doesn’t like that sort of thing.

You might have wanted to separate the Servo power from the Pixhawk power too.

Best regards,


Thanks Gary, I will do that - next time! :wink:

The damage is done, but would like to know where do I go from here?

Can the Pixhawk be tested & repaired, or do I have to buy new one?


Hi Miro,
I’m pretty sure you need to contact 3DR tech support and tell them what happened.
They can help you.
Best Regards,

Thanks Gary

… will do for sure, but I’m waiting to register my s/n … and I do not know where to find it … :wink:
My lack of training in “discipline” is punishing me… I told my self (just one try, up & down) in expectation of a positive rush of accomplishment for modifying and making amounts for my retractable tripod! … did I mention it is my first build, or any contact with the technology, making a heavy lift X8 with 3x gimbal for heavy camera & and a smaller one for flying practice?..on a monthly income of 300 USD!!!..yeah I know, you can laugh!..I do, all the time! :wink:

Hi miro,
Your budgets even tighter than mine,but I understand completely.
I don’t know where the Pixhawk serial number is either although I have one.
Probably on the board itself inside the case.
But I know they will accept the Invoice number date and name of the purchase as well.
I would suggest that you check the power module output to see if it still shows 5 volts.
If it does still show 5 volts, the Pixhawk is most likely damaged.
If it doesn’t, the power supply module may be blown and it is barely possible the Pixhawk itself is OK.
It isn’t likely, but worth a check.
Otherwise I would suggest you send in both for repair. :frowning:
Best Regards,


It’s not the power module as the PX4 behaves the same connected to usb…it is going for repairs, but USA is long way away!