Backlight turns off after Vizio logo goes away.
I have a Vizio P55-C1 TV (Just a 55 inch version of the P65-C1 TV, has roughly the same internals too)
Starting from a fresh power cycle, the TV will start up and the logo will be displayed and lit up just like it should. Then after the logo goes to go away, the logo goes away and seems to try and turn the backlight on, but a very very very faint flicker occurs and the TV is now dark. The image is still being displayed (Can see it with a flashlight if held up to the screen) but there is no backlight.
Things I have tried:
- Power cycling
- Lower brightness and set picture mode to Standard
- Opening up the back and inspecting for bulged components and/or burned ones. (There is no visible damage on either side)
I have also opened up the TV and checked the power lines coming out of the power supply. There is a 19V line going to the main board which is perfect at 18.9V.
but the 10V lines going to the 4 LCD Driver in the middle (shown above) start at 9V when the TV turns on, and slowly drops to 0V. This seems to be the source of the problem I assume but I just wanted to see if anyone else has any other ideas.
The TCON board and The Mainboard both have the correct voltages on their power lines so they seem fine.
I’m planning on replacing the power supply if it seems that I have diagnosed it correctly.
I’ve repaired 3-4 TV’s in the past so if there is any voltage lines or other things that anyone wants me to check, I can. This one has just stumped me.
Questa è una buona domanda?