Jim Macklin wrote:

There is a train of thought that pulling CB as switches can
weaken the springs and latches that make the CB function. I
doubt that is a problem with modern designs. I'd have to
look at the TSO, but imagine they are good for thousands of
cycles.

At one time Cessna and Piper were using flush CB. I do know
that in the Beech aircraft we pulled CB all the time, on the
landing gear, flaps, radios, and never had a CB failure.

If I were instructing in a G1000 airplane, I would first use
aux. power and run the G1000 on the ground, pulling CB and
noting what failed and what did not. I would then start the
engine and do the same while on the ground. Then I'd repeat
it in-flight, noting any differences and creating my own
checklist and reversion list.


I would sure clear that with both Garmin and the aircraft manufacturer
first. You might reduce the life of certain components by doing that.
These are not electromechanical devices at rest like flaps or landing
gear. Some of this electronic stuff likes to go through a shutdown
sequence. This may, or may not, apply to the G-1000.

My experience with Garmin stuff is limited to the 530. I would never
pull the CB for it without first turning the unit off.