Electrical Questions? Ask an Electrician Online.
Hi, I'm Mike G and I'll be assisting you. The problem could be one of several possibilities. Bad switch, bad lamp holder or wire loose making a bad connection. You'll need a 2 wire voltage tester to verify which it is. Do you have one?
The wattage of the lamp isn't what's wrong. All you can do is make a few simple tests with a 2 wire voltage tester to pin point what's causing the failure. Testers are available at any home center for under $20.00. Get one and we can continue. You need to test, not guess.
There should be access to the wiring from below on the interior of the hood. You need to test the light switch for voltage to ground to verify it is or isn't working. If it is, then an inspection of the wires to the lamp holders is next. Having 2 lamps, I would think they are OK. Having both fail would be unusual. Let me know how you make out.
Unlikely it is the lamp holder for both not to work. Switch or wiring is what I expect you'll find.
To test the lamp holders you would put a probe on the hot pin and a probe to ground. Then you would test hot to neutral. Nothing on the first test indicates the switch or the hot wire as the problem. The second test would indicate an open neutral, probably a wire connection came loose.
The black wire is the hot wire, the white wire is the neutral. Both have to have good connections to the wire feeding the unit. If either are not connected it wouldn't work. When installed a connection may have been not made up properly. Wire moves when it heats due to current in it. If the connection isn't solid the wire may desperate and open the circuit.
Check underneath, the controls should have access.
Good luck. I went online to get info on that hood and found it discontinued and nothing on troubleshooting.