Backup camera works intermittently

VABAM

If I’m reading your description right, the backup camera transmitter is only on when the car is in reverse. If this is so I think that the backup camera receiver times out and turns off after not receiving signal from the transmitter for a certain period of time (many wireless systems do this). This might explain why it only works right after you turn on your car. First read the install directions for the wireless system and make sure there isn’t something in the directions saying that it needs a constant source of power while the car is on. If it says to hook it up to the accessory or ignition power then hooking it up to the tail light for power might be the issue. If the directions are vague on what is a suitable power source then I would wire in a temporary power source to the transmitter that stays on when the car is on to test this.

BTW what is the make and model of the wireless backup camera system?

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