i don't know, but see your parts and costs at:
http://www.repairclinic.com/0003.asp
and lots of encouraging words always at:
http://www.fixitnow.com/
and if it was up to me i would consider giving the bulb power
constantly. i need a nightlight anyway and i enjoyed the old microwave
feature where the light stayed on until the food was removed. i can't
tell you how much forgotten cooking has been wasted at bedtime since
that feature vanished, at least from the models i've been buying.

kmdguy wrote:
Hi there,

I've a Whirlpool Microwave (model MH1150XMQ-1). It is 1.5 years old.

Recently the cooktop light bulb quit working and I simply thought it
had burned out and went out and replaced it. The new bulb did nothing.
Hmmmm. So I opened up the underside panel to check the socket for any
problems. Using my circuit tester I determined that there was no power
coming through the wires to the cooktop light socket. I plugged the
socket into the wires that go to power the turntable and the socket
indeed works fine (of course only when the microwave is engaged). So,
I'm not getting any juice through the wires that clip to the cooktop
light socket.

I'm not sure how to open the unit up any further to check to see if
something is visibly amiss with the board that feeds to the socket.

This unit costs about $150-$170. Is this a problem worth fixing or is
it something I can possibly fix on my own? Any input is appreciated.