Interference filter (stabilizer) for reversing camera (low current)

Hello,

Please help me to install a noise filter for the rear view camera in the car.
I have such a problem that there is no place to run a separate power cable to the camera (I barely fit the signal) so I plugged in the lighting of the board. There was of course a problem with interference caused by the alternator.
I bought a suppression filter, which probably does not work because it works in the 3-8A range, and the recording lighting + camera is max 15 W
In addition, the computer disconnects the voltage from the board lighting after plugging it into the system.



And now my question is whether my diagnosis is correct and are there filters operating at a lower current?
I would not want to run a separate wire from the relay because it would involve the need to drill in the flap, and I would like to avoid it. I can plug into the power supply circuit of the board.
Thanks for the help!

It is possible that the backlight circuit is pulse controlled (PWM) or / and also has overload protection. If you gave an additional load of 15W, then there is no reason today that the circuit, which normally has 3-5W, is protected.

The camera works without this filter at idle elegantly and the plate lights also shine, unless this filter generates additional load?