I have had my microwave for roughly 3 years. My halogen bulb went out for the first time recently and I replaced it. It went out again within a couple weeks and I replaced it. It went out again within the month and I replaced it, and this cycle keeps happening. I have replaced the bulb 5 times now, with the last one only working a few days. What more can I do?
I would first check the polarity of the power supply. If the hot wire is hooked up where the neutral should go, this affects the power supply on the main board and could cause harm to other on board components including the halogen lights. If the polarity is correct, I would replace the halogen light power supply which is the main board 4781W1M325N. It could have a component that is slipping further and further out of tolerance and is in need of replacement, which would explain the lights having a shorter life after you replaced them.