red light
warning light

But there was no warning light in the window of the third and last place.

Both of the red warning lights had gone out on the trouble board.

And at the same time a red warning light lit up.

A red warning light on the wall began to glow.

He waited until the warning light turned green, then followed.

The warning light in his eyes pinned her to the wall.

One of the warning lights was found not to be working after the crash.

The guy on watch flashed a warning light, but there was no response.

During the summer the red warning light on the top of the highest tower, some 226 feet up, went out.

In our lives, it was like a great big red warning light blinking on and off.