Hi,
Not quite sure what you mean with your question.
The LCD screen is a complete module and responds to signals sent from the motherboard in the camera. It doesn’t have a separate control board that can be replaced. The whole module needs to be replaced if it is faulty. The motherboard controls most functions of the camera.
Also the LCD screen’s backlight is not a separate component. It is an integral part of the screen itself. If the backlight is not working and the problem is not in the camera’s motherboard backlight power supply circuit or the cable connection between the motherboard and the LCD display then the LCD screen module will have to be replaced.
Here’s a [https://www.youtube.com/watch?v=x74dQI4NYW4|video] that shows how to replace the LCD screen in the camera.
Replacement LCD screens are available online. Just search for ''Canon T6 LCD screen'' to get results for suppliers of the part. Here’s a [https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2499334.m570.l1313&_nkw=canon+T6+lcd+display&_sacat=64352|link] just to give you an idea of the cost of the part.