Hit the roof -- stop when you do that! (3,3)
I believe the answer is:
see red
I believe this is a double definition.
'hit the roof' is the first definition.
(both can mean to become very angry)
'stop when you do that' is the second definition.
(traffic lights)
(Other definitions for see red that I've seen before include "Be annoyed" , "Be suddenly angry - like bull?" , "Become enraged" , "Become angry as bull might" , "lose control" .)