I was thinking, it could refer to removing / placing screws as "screwing up" ergo "Please, screw up only with the human tools"

"Dumb brakes" = user error causing damage (yes I know when to say break vs brake - the whole point is a "translation failure" joke)

For a safety warning sign, I came up with "pancake accident" and "die electric" (self explanatory)

 

For an elevator, I came up with one where the laundry list of forbidden acts, also would make some people wonder what kinds of "repairs" has this thing suffered to get that bad:

Caution: Do not be Tigger / Pogo Stick bouncing or dance while the moving elevator: it may be broke stuck!

Caution: do not more than buttons calling, not more than 3 floored buttons at the same time, it may broke stuck the elevator!

Caution: do not redundant over and over again, the buttons over and over again: the elevator may broke stuck!

The last two are just the standard things "Don't use during a fire, or tornado warning"

If the building is screaming everywhere strobe lights run away event, please do not the elevator, runaway the stairs, during runaway strobe lights with the buzz buzz buzz

Please do not the elevator, during the shelter lower floors to avoid the spinning around wind it sucks - the stairs if need to basement shelter the major storm, it sucks