How to troubleshoot extruder motor

My K2 has been sitting idle for 3+ weeks now, with the extruder motor presumably dead.
It doesn’t rotate at all and it happened right after it started reporting problems with the heat fan.
No matter if I try to use the cfs, CP5 or CP6, or even from the touch screen, the extruder motor is dead.
I have been trying to reach tech support with every known to me communication methods with no response.
So, my last hope to find out what’s wrong (besides using other means to protect my consumer rights) is the community.
Are there any troubleshooting methods to try and pinpoint if the problem is with the motor, the board or perhaps the software?

Is the material sensor light on? I found 2-3mm clear plastic shards holding the sensor swing flag and locking mine out. Also, I assume you are watching the servo drive wheel dots when you manually try to work it? And, check the entire length of used 1.75 mm plastic for grinding out spots from the servos fighting each other if they are out of sync one of the 3 will rip a spot. And then it is amazing the place will end up in the drive and give a jam error code for blockage. I had to power off over 2 minutes if the firmware dropped the servo or missed one in a command set causing the conflict to get the servo control to return. I dislike that there is no firmware reinstall or revert to an earlier version if unstable or corruption is expected through the PC. Through the thumb drive it recognized any firmware new or old as an upgrade and wanted to replace it.

Thank you for replying and for your troubleshooting suggestions and ideas.

I removed the extruder half along with the gears so I have clear sight of the motor gear itself. By using a thin piece of plastic, I’m blocking the optical sensor to simulate filament presence.
Then I heat up the hotend to temperature (say 200c) and hit extrude from the touch screen while I’m watching the extruder motor gear not rotating at all.

I don’t know if there’s something in klipper config that could potentially prevent it from sending any movement commands to the extruder and I don’t want to “mess” or “experiment” with it without creality’s blessings :grinning:

So, new ideas/suggestions are more than welcomed