Another repair is done so far. This Unit (on the right) not heating at all. Going thru the diagnostic process couldn't find anything significant. Warning lights or error codes won't come up. And the way to test is just to get your multimeter up and wiring diagram to detect the breaking point in circuit. End up to find out the broken motor control switch aka centrifugal switch. And for sure all others elements were checked and rechecked thoroughly. Here is a picture.
The contact surface (the one in the middle, second from the top) lost ability to touch the one next to it. The small copper piece (round shape) fell off the copper stripe or plate. And there are two possible solutions.
...Power it up, Start button pressed and finally heat came back as it supposed to be!
Thanks for reeeading!