It is hard to troubleshoot because on the ground the temps are warm and impossible to duplicate. I can see the crews prior to this flight not writing up the fault if it happened a lot?????????????
I can see it being hard to troubleshoot because it is not in the logbook. Aircraft maintenance is performed in all sorts of weather conditions and generally speaking problems will get solved. It may not occur on the first attempt but it will get solved. The most important thing is that the problem is documented. That is the starting point.
Circuit breakers are intentionally placed in the overhead and back wall of the cockpit, while the devices they control are all over the airplane. They put CBs in reach of the pilots, and say, "Don't touch?"
It would save a lot of wiring and cockpit real estate if the the CBs were near the devices, or near the power source?????????????
Greybeard. You might have noticed that the circuit breaker panels contain information as to which bus the circuit breakers are connected to. That is because the busses are right there at the circuit breaker panels. Putting the circuit breakers near the devices they power would not be of much help to the crew.