Nudges:
There are a number of words in the grid with “on” in them, but that’s not what you are looking for
There are four themers
What might you be testing if you said the title phrase?
A title variation that was under consideration was “Is this thing off?”
Considering the themers, if that thing you were testing is off, what does that leave you with?
Can you find an alternative answer for what remains?
The meta answer is seven letters long