On Friday, December 20, 2019 at 3:09:49 AM UTC-5, Oumati Asami wrote:
The light in the laundry room stops working after worker had worked on
the ceiling in the next room.

There are two wires coming in to the light (or one in one out). Before I
flip the switch, both wires are not charged as tested by a tester. After
flipping the switch, both are charged. Yet, the light just won't light.

I removed the light and plug it in to a socket, it works.

Question:

1) did the test (both wires not charged and then charged after flipping
the switch) I do make sense?

This test is with the light removed? You have one cable, with two conductors
plus a ground wire? By charged, do you mean that you have 120V on
both, or some other, lower voltage? What are you connecting the other
side of the meter to? Ground?






2) how could the work in the other room affect the light next room? I do
see that there are three wires in the switch box, none of them neutral
or ground. They are all live wires. Two on one side of the switch, one
on the other side. The two are charged, the other is only charged after
the switch is flipped.