At the end, we connected the all 4 esc on another FC and confirmed the problem comes from the pixhawk. I guess we will buy another FC. I filed a support ticket to 3dr without any answer, this is sad.
Crossing message on the the forum I find…"
It wasn't the PWM throttle value being too low :(
I did get all the ESC to init and motors to start in stabilize mode (was in althold before as a default mode) but 1 of them didn't start right with the others, it took him like 10sec more to…"
"I'm off the office for a few days, so I can't test for now. But i'm pretty confident you put me on a track with the low PWM throttle. Out of pure memory, I think my lower throttle pwm was around 975. I found it strange while setting up the failsafe,…"
I also tried to use the Pixhawk all-at-once calibration, but only 2 out of the 4 esc starts the calibration process.
It's pretty much following the same pattern as when I use the switch to unlock the quad, it only…"
Hello,We are building a new quadcopter, the relevant parts for the problem are listed bellow:Motors: Tmotor U3 ESC: Tmotor Air 40A (no BEC, 600Hz)BAT: 4SFC: Pixhawk 3DRTX/RX: Futaba 10J / Futuba 2008SB, connected in SBUSEDIT: Firmware(s) tested: 3.2…