Rep Power: 0

Hello all, i need some advice on my home mechanics...
I've got a 1997 Honda civic 1.4 i s 90hp hatchback, last year i drove it into a tree... After a while of waiting i finally received the pieces i needed to rebuild what i broke (triangle, suspension triangle, drive shaft, wing, light and bumper), everything is fitted on properly, but the engine Will just not wake up, even just after the crash it wouldnt start, and since the engine has not been touched by the accident and all fuses are alright, a mechanic back when it happened told me that there should be just some sort of engine security trigger or something of the sort that i had to find to unblock it... Anyone have any idea If there is, and where it is?
Thanks a bunch