Are you having a problem with the stove vent hood? If so, the Halogen lights can be replaced by removing the light fixture from the fan housing. The fixture pulls out to access the bulb. The fixture is held in place with spring clips that are integrated with the housing. Had the same problem. The fixture came out with a bit of persistence. However, on first inspection that fact was not apparent. The fixtures are very tightly held in place by the clips.
The bulb was not easy to find. Actually it probably is, if you know what to look for. I took the bulb to a "We sell all Light Bulbs" store and they matched it up for me. Suspect they are available at marine supply stores as well.
The field force adjustment tactic is often employed when the correct approach is hidden from a logical inspection. It may be best to refrain from that approach and use a flashlight until the solution is more obvious.
If both lights fail to function, then a wiring or switch issue may be the problem. It is my understanding that one owner modified the fan assembly to improve performance. I assume the whole unit was removed to access the internal components. That would be my approach to a circuit issue.
A flashlight would be my approach until I returned from a trip.
Pat