Newbie destroyed third pixhawk

Dear community,
after several sucessful FPV project with F3 racing FC, i switched to a pixhawk project. 5 min ago i destroyed my third pixhawk 2.4.8. The symtons:

  • Switch is blinking red
  • Status LED is off
  • Some strange noise comming from the speaker. An USB connection is not longer possible.

Same problems with my other 2 pixhawks. I believed that i bought cheap china stuff…but 3 times?
I assume power problems ?

Power is comming via the PDB directly from the PDB. No BEC from ESC. No power connection between receiver and Pix…

My config:

  • Pixhawk 2.4.8
    -Pixhawk PX4 5 in 1 PDB
  • Bulltec Multicopter 30A OPTO BLHeli
  • T-Motor 3508
  • Separate power switch for Lipo

Any idea ?

Cheap China Pixhawks have worked well for many. I would suspect the 5in1 PDB before the Pixhawks. Power switch for Lipo? What switch? This is not advisable if it’s carrying all of the battery load.

What power module are you using for the pixhawk?

I have had cases where the FC would not boot up properly and would utter strange metalic sounds from beeper when the power supply was insufficient, i.e. the voltage provided by power source was too low. Can happen with faulty power supply or if you try to power over USB and the USB port of the laptop/Pc cannot provide enough current (or the cable is poor or too long).

As fnoop and dave indicate, I’d check wiring and/or power supply and potentially replace them (one after the other) to eliminate possible root causes one by one. I doubt it will be the FC itself… I have used the same type successfully several times.

Another thing you can do is try use a voltmeter and see if you can measure the power voltage provided to the FC, it should be >= 5V…

Also I’d be careful with switching the main power supply, assuming you have a quad with 4x30A max (your ESC rating), if you were to demand full throttle your switch would need to withstand 120A…is it rated for that?

Good day,
for pixhawk 2.4.8 better use the original or compatible power cable. if you want have a good redundancy you can power it through the servo rail, on the output of the sbec you must solder first a capacitor with a zener diode so will provide stable, 5.30v.
I don’t trust a lot in the Pixhawk PX4 5 in 1 PDB.

1 Like

Right. The Voltage from a power module suited to Pixhawk should be at 5.37 volts ideally.

Good morning,
so, i will replace the pdb with the original cabel to power up the pix. I have the feeling that the problem is in combination with using power from usb while configuration and samtime power on from LIPO. Is that a problem ?

Any idea how or where to repair my demaged pix ?

But anyway…thx a lot for your hints…


I inserted a power switch between lipo and pdb to avoid disconneting the cabel.

5 in 1 PDB :

Hmmm…good hint. i did not think of that. Of course i switched on with max throttle while calibration ESC… I will remove switch and PDB and will buy my fourth on :slight_smile: Hopefully my last one ! Thx Andreas

That’s a good 1st step. The contacts on a 20a switch will fail as max current draw will likely be much higher than that at times.Then your craft will rapidly return to earth and you could have more damage than the Flight Controller. A good quality Power Module is recommended. I have a few from mRobotics and Mauch makes good product also and is widely available.

Good day, i can advice you to buy the mro classic power module for your new pixhawk, before connect it to the pixhawk just check the correct voltage, in my opinion you don’t need a power switch on the cable.
Its not easy repair the components of the pixhawk,