Why can't mobile DVR start when the cables are connected?

The VCR should also pay attention to the hard disk lock.

Why there is no image on the monitor when power of the camera and mobile DVR is connected ?

Check whether the power supply is connected to the 12v position. The power output of the mobile dvr recorder has two voltage options: 5v and 12v.

Why the data cannot be tramsmitted under 4G network?

If data transmission doesn't work, the possible reasons are as follows: · No 4G antenna connected; · D SIM card inserted; · The PC configuration is incorrect. For example, the gateway router does not do port mapping. · DVR: The wireless setting part of the setting menu is incorrectly set. For example, the wireless dialing is not turned on, the 4G protocol settings are incorrect, the access point settings are not equal; the central serve part of the setting menu is incorrectly set. For example, the center IP setting is incorrect.