During an IPC yesterday with the owner of a 1993 F33A Bonanza, I surreptitiously pulled the "LDG GR POS" circuit breaker in an attempt to see if he would notice the lack of green lights as he lowered the gear at the FAF. In the attached picture, this is the 4th one on the top row, a 5A breaker. I thought "LDG GR POS" meant "Landing Gear Position (lights)" and expected the gear to go down but just the indicator lights to not work. Well, he did notice, because the gear did not go down either. Good on him for noticing that. So we still had an effective training event. If I had pulled the 30A "LDG GEAR" breaker (first one on bottom row), I would have expected this behavior. But not with the "LDR GR POS" breaker. So, one of two things - either I don't understand what "LDG GR POS" means here, or I don't understand how the 1993 F33A gear warning system works. Or, I guess, something's wrong with his airplane. I did look in the POH and it's not very detailed on this topic. I did not see a diagram of the electrical system in there either. Anybody have any knowledge about this and can steer me right? Thanks.