help for video when the car is moving.

Hello

what is the negative wire to connect the car to watch the video when the car is moving.

Thank you for your help

Number model: S07
Versio MCU: MTCB KLD2 V2.77 aug 26 2015
Version android: 4.4.4 10082015
Kernel version 3.0.36+ @ chun roo-book # 817
Build Number: RK3188 eng 4.4.4 10082015
CPU: 1.6 GHz armv7 (X4)
Memory: 1024 MB

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