I have a wall-mounted over-the-range microwave oven that is completely non-operational at the moment; from the user's point of view, it's as if it were unplugged, but it is. Unfortunately, access to its plug requires unmounting the oven. Furthermore, the circuit breakers in the fuse box are not labeled.
If I could get any response at all from the oven, I could use this response to find its circuit breaker by trial-and-error. As I already noted, I can't get any response from the oven by using its standard interface (the buttons on the front panel, opening the door, etc.), but I can remove the oven's front panel, and have a parts-list diagram. So my question is:
Is there some way (possibly with the aid of some suitable tool) to get a clear response? (I.e. a response that will change unambiguously when I toggle the right circuit breaker.)
(PS: I realize that there are other ways to deal with this situation other than identifying the oven's circuit breaker, but I'd like to know of any possible answers to the question above.)