On 12/20/2019 2:09 AM, 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?

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.

The most likely is that which Clare noted before; the neutral in the
worked-on box wasn't reconnected.

If you can see the obvious issue there as he suggests, then you're good
to go. If not, since the issue appears to have been caused by the work;
I'd suggest get them back to fix the problem they created.

What was the purpose of their work just out of curiosity (altho that
might have some bearing that might make understanding what happened
simpler from afar).

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