The yellow exclamation mark is a warning light, this light comes on to indicate that something is wrong with a part of the car that should be fixed.

In your on-board computer, there is a warning content that will have a specific tip in it.

Here it's just indicated by a yellow exclamation mark, which represents a number of situations, it could be running out of gas, or it could be running out of glass water, which you need to check the car computer to confirm.