Brushless motor slows down over time

There are 4 Skywalker 50A esc and 4 brushless motors connected to Pixhawk. They were working fine before the accident. Only physical damage was taken in the accident, no electronic burns or disconnections occurred. After fixing the physical problems, I connected an ESC plugs positive and negative lead to the negative terminal while re-establishing the connections. And when I put the battery into the circuit, it burned for 5-6 seconds, smoke appeared. It melted the plastic on the ESC, and the cable connected to the Pixhawk melted. I hope it didn’t damage the electronics inside the Pixhawk. At that time it was connected to the 2nd or 3rd output pin on the Pixhawk. I ordered another one from the same ESC. And this time I set up all the connections correctly. But now the other 3 engines are running smoothly with the signal received from the control. There is something strange about one of them. In order to start this engine, I have to give the throttle more from the remote. Then it starts to work but gradually loses its power. It’s slowing down. If I power too high it doesn’t slow down, or I don’t notice.

I tried these:

  • replaced the motors, the problem was still in the same place, it wasn’t caused by the motor.
  • replaced the ESCs. It was still in the same place. It’s not from ESC.
  • replaced the motors from Pixhawk. The problem was not fixed. If, first motor connected 5, second is 6, third is 7 and fourth is 8, problems occurs pins 6(second motor). If ı connect like this, first motor 3, second is 4, third is 7 and fourth is 8, problems occurs pins 4(again second motor). I changed motors but not fixed. Still continue.

What can ı do know, What should I try?

C’est peut-être un peu tard, mais si seul le moteur 2 est impacté suite à tes expérimentations, serait-il possible que les liaisons électrique de ce moteur soient touchées de manière non perceptible ? Les fils sont les seuls éléments que tu n’as pas évoqué? Au cas ou…

have you calibrated the ESCs?