V2 pro with smart cable

Parking monitor not working with smart cable hooked up properly , with car off I can turn on and off the dash cam , when I try parking monitor setup it gives me two options g sensor and time lapse, I press g sensor , I shut off the car the unit powers down , I shake the car the camera and nothing , should the camera turn on when it senses vibration or impact , I shake rattle the car and camera and nothing happens , I believe the camera should turn on and it's not