Chosen Solution
Replace the main board.
@jafinch78 this “did notice what looked like discoloration “ could be an issue with your LED power board. You want to go ahead and post some good pictures of all of your boards with your question. Use this guide Adding images to an existing question for that. It will allow us to see what you see. You will have to have a multimeter to see if your power board as the voltages that are required to run your TV. There is not to much information about your Proscan so we will have to rely on your troubleshooting skills. UPDATE 08/11/2018 here is the schematic for your power supply. Different revision but it will still give you the same ouputs etc.
No schematic seems to be available for your main board B.ZRAT3C-5 @jafinch78 check the jumper CN4 on B.ZRAT3C-5 8374 and see if it is on 5V or 12V. Any chance this could have been switched. Yours looks like it is at 12V try to switch it to 5V. Keep your fingers crossed and see what you get. UPDATE 08/12/2018 Looks like the T-con board runs kind of hot. Check the fuse to make sure you got continuity as well as power when your TV is on. Check to make sure it is just the thermal pad that is crooked and that there are not issues with the processor
According to your T-con board your display panel is a T315XWO2 VL Here is the datasheet for that. You may need it later on Microsoft Word - T315XW02_VL_v0_4_0118_Final.doc Interestingly enough the T-Con board as well as the Inverter V266-001 are identical to a Sony KDL-32L4000 I am going to check if the Sony manual will give us more information.
There should be some surface mounted transistors on the inverter board that may be shorted. These will be small black squares with 2 regular pins and a short cut off one in the center (attached to the back/tab). Check these for a short. You may get lucky and only need to replace one or more of these. Dan
