First of all, the camera needs continuous power supply to work.
There are two solutions in this case.
1. Buy hardwire kit & fuse tap and draw power from fuse box directly
Connect the camera by hardwire kit to your fuse box directly, BAT red cable to a constant live port, and ACC to an accessory port, so when the car engine stops, the camera gets a signal from hardwire kit and sends the camera to the parking mode automatically.
Click this FAQ for hardwire kit installation guide.
2. Use an external battery pack as a power supply
Click this FAQ for an external battery guide.
Note:
- If you use car charger and your cigarette port is constantly live even when the car engine is off, there is a risk of battery drainage;
- If your car battery fuse box has no accessory port (which loses power when the engine is off), there is no way to enter parking mode with hardwire kit.