French Road sign?

Question

I was in France the other day and saw one of their road signs and could not work out what it ment! It was a picture of a car with what looked like an explosion on the car bonet. Any ideas?

Answer 1

Road Closed to Vehicles Transporting Flammable Materials.

Answer 2

A hill is ahead and your engine might overheat if you leave the A/C on.

Answer 3

suicide bombers ahead

Answer 4

you know how people load stuff and tie it down to the roof of their car? yeah... its that