How have you connected your PH4 to the motors?
The PH4 provides seperate outputs for the I/O PWM Output and the FMU PWM Output.
You need to use the I/O PWM Output.
Also note that PH4 uses 3.3v PWM signals, so be sure your ESC’s will operate at that voltage.
Update your firmware to this one: http://firmware.ardupilot.org/Copter/stable/Pixhawk4/ by downloading the .apj and then load from file in Missionplanner. It would be a good idea to then update the bootloader so Missionplanner can identify the board correctly in the future.
As Mike suggests, check which outputs your motors are connected to on the power board, and which ones you’ve got connected between the PH4 and power board. A photo and your parameter file would be useful.
OK, Thank you. This solve my problem.
In my understanding, I had assumed that the ESC will be connected to the FMU.
Everything works fine on the I / O PWM.
If you want to use DShot, they need to be on FMU pins, but you can do that by connecting the IO socket on the PDB to the FMU outputs on the flight controller.