GE Microwave Repair
GE Spacemaker Microwave
Microwave running but not heating food
The problem can be in either one of the door switches, depending on how the unit is wired. Or even more common would be the circuit board or the relay board on this type of unit.
It is extremely important to be careful when working on microwaves because they do store energy and you don't want to get electrocuted. Even unplugged, the capacitor holds a charge and if you touch the wrong wiring, it can cause problems.
Normally on this particular unit, if you do access the internal parts of the control panel, there is a circuit board located in there and four wires that plug into the board. The red wire should be the power supply. This wire is probably burnt on the control board.
Most times, you have to replace the board. A new board for your microwave can cost in the range of one hundred and twenty to one hundred and fifty dollars.
For an older microwave, if might make more sense to replace the entire unit than to spend the money on this GE microwave repair.
2003 GE Advantium Microwave Model SCA1000D
Smoking and giving off an electrical smell
The Advantium is a microwave/broiler unit combination. So as far as the smoking goes, it could be a lot of things. It could be just the element (part #WB21X10055) has burned out or it could be a transformer or a circuit board that's overheated and you're getting the electrical smell.