Microwave / Range Hood - light underneath Popped

[HanKdKranK]

Hey all:

We have a Whirlpool under counter, over stove microwave (vented outside). I replaced the underneath light bulb about a month back and it quit again today. My wife was replacing it and it popped, blew the glass bulb out of the metal socket/base, and won't work anymore. I think that when she moved the bulb it shorted out inside the bulb assembly and destroyed some circuitry inside the microwave. I tested the leads to the bulb socket and there is no power there. The light switch (soft touch button) still beeps like it's doing something when you push it (it has three settings, off, bright, dim (night light)). Anyone have any ideas? Please and thanks, HDK

[Mike rock]

2 possibilities: Did you put in the right voltage bulb, ie put in a 12V bulb when its suppose to be 120V? or possible it uses halogen bulbs and touching it with your fingers left oil on the bulb resulting it in popping. In any event if you have no voltage at the socket, something blew inside.

[JerryM]

If it's anything like my Sharp OTR microwave, pretty much all the circuitry except the high power stuff is on a single circuit board. If something is bad on there, you either have to isolate to the defective part, or replace the board. If that's beyond your skill set, an appliance repair tech will probably want to replace the board. At that point, you might be talking about the tradeoff between the repair costs or buying a new microwave.

My Sharp has 2 bulbs, AC power is switched to them by relays controlled by the microprocessor on the board. If your setup is similar, and the power was shorted when replacing the bulb, it's possible that either the relay contacts are bad, or circuit board traces leading to or from the relay(s) could have opened up.

Jerry