go dark

phrase

1

: to become dark

The room suddenly went dark.

2

a

: to stop operating or functioning : to shut down

Most Salt Lake City restaurants go dark on Sundays …

—Kurt Repanshek

Andy Beal was one of 220 million subscribers to Skype … who saw the service go dark on Aug. 16.

—Stephen Baker

In the end, the heart stops, the cells die, the neurons go dark …

—Joshua Ferris

b

communications : to stop broadcasting or transmitting : to go offline

… Lt. Col. Steve Russell of the Army's 4th Infantry Division ordered his men to "go dark" and roll their Humvees up to the edge of a lone farmhouse here.

—William Booth