Re: GE Stove hood
First, test each socket with a bulb that is known to work, if it's still no joy, then it is possible that it's dirty sockets, but more likely a bad wire connection at or near the switch. It is possibly even a faulty switch. If you are not familiar with wiring, I'd leave this job to someone more experienced. If you've got some basic wiring and handy skills, then dig in and see what you find.
If you clean the sockets, make sure to turn off the breaker that powers the hood, never trust that the switch is functioning or you could be in for a very rude surprise!
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!