My 9 year-old Electrical Matag dryer did not start, after I reset the circuit breaker, the circuit breaker trips when I plug in the power cord of the dryer.
The resistance between two ends of the start switch(not pressed) is about 2k ohm when dryer door is closed, the resistance is open when dryer door is open. There is also about 2k ohm between netural(middle) and one end of the power at terminal block. Any idea what's wrong?

It sounds to me like there is a short in the start switch, perhaps the housing is carbonized from 9 years of arcing each time it opens and closes. I think the start switch should be hot on one side and the other side connected to the neutral through a relay coil, open in the off position.