One motor of 12 not starting

I have a pixhawk 4 running a dodeca hexa setup. I had a motor and esc go bad after a prop was hit. I have replaced everything and verified the motor and esc work fine but this motor will not initialize when arming the 12 motors. I even ran a new signal wire and ground but the motor is acting like its not seeing the signal wire when the battery is connected. Is it possible the pixhawk hardware board has been damaged? I have tried everything and can not think of any thing else to try… Does anyone have any ideas?

It could need calibrating so it is expecting the same range of PWM as the other ESCs

Thanks but they are all factory set and identical and it runs fine through an RC setup, just cant through the pixhawk

What are the ESCs exactly?

What does MissionPlanner motor test produce when testing that motor?
Set LOG_DISARMED = 1 and try to arm or run motor tests then LOG_DISARMED = 0
and you can upload that .bin log file somewhere and share a link.

Swap the sig wire at the flight control with another working motor and see if the problem moves or not. That way you are testing the sig wire, esc, and motor all at once

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Yes perfect! Thank You I will try. The 1st 8 are all on one connector but I can swap 7 and 8 in the connector. I appreciate it

They are Tmotor Alpha 120A 12S and the test does not spin it but I will try as you say… Thanks

The connector with a black wire and white wire are the correct signal wires - I guess you have a whole bunch there all plugged in correctly for a reference.
People can get confused about which connector and wires are the throttle with those ESCs.

Quick Update… I swapped the 7 and 8 motors signal wires at the board output and the problem move just as you suspected. Thanks for the suggestion. I’m a little bothered by the fact I did not think to do so on my own… I have a new board on the way!

Glad you found the cause, im surprised that the fc output has failed but it can happen i guess. New fc will fix it. Don’t worry about not seeing the obvious, there’s so much going on with setting these up that the simple things get lost in the woods sometimes. I blew a new fc and gps up through reverse polarity supply, and I do instrumentation and controls for a living…