Stop! Time to get out without wearing straps (5)
I believe the answer is:
reins
'straps' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
(Other definitions for reins that I've seen before include "Straps for controlling a horse" , "Power to direct and control" , "Checks" , "Horse's controls" , "Harnesses" .)