I am in the military and came back from a month overseas and my 3 prong electric dryer would not start. I am an electronics technician (radios) so I am quite experiences with electronics and theory (although DC is my strength).
I checked all the routine no start issues, door switch, start switch and thermal resistor all have continuity when isolated. I checked voltages at the receptacle and on the distribution block of the dryer hot to hot-240V, neutral to hot A-118V, neutral to hot B-123V and nothing would happen when start was pressed. I hit start and tried to spun the drum, nothing. I ended up pulling the front panel completely off and removing the drum and checked that I have 118V on M4 of the motor switch. In order to check the motor I created a test cable from an extension cord and (cut the female end off and stripped the ends) and connected it to the dryer power distribution on the hot side that controls the motor (not the heater) and neutral then plugged it into a standard 120 wall outlet and the dryer started up like a champ so I knew the motor was good. I then plugged the original cable back in and tried to start it and it didnt work. I then opened the motor switch and the voltage all looked good. I then manually shorted the relay for heating circuit on the motor switch and and the coil heated up. I then ohmed out the timing switch and it was good.
I then opened the receptacle and put my multimeter probes on leg A and neutral, it read 118V and when I pressed the start button the it dropped to 0V and leg B was at 240V. I thought it could be a open neutral (although I dont have much experience with neutrals being a DC guy but I am familiar with electronic theory) so I connected my multimeter between the common (ground) pin on the door switch and the bare neutral wire on the service panel and it read 1.3 ohms so there is neutral connectivity throughout the circuit (I also verified that all grounds had connectivity with the neutral in the service panel).
I am now at a loss as to where to go next. I really don't have an idea of where to go next as every thing else in my apartment works as it should and I don't have the funds to hire an electrician or a repair man. Any help or suggestions would be greatly appreciated.