It shows where to put something in the car, etc. (5)
I believe the answer is:
caret
But I can't explain it at all! Could you help me understand?
(Other definitions for caret that I've seen before include "Indicator of omission" , "Proofreading sign for 'Insert'" , "Weeding tool" , "It shows what to put in" , "Proofreader's sign of omission" .)