Gave up on my last project and decided to take on this Vizio. This TV shows no signs of life other than having my 5 volt STBY. The Vizio logo doesn't even illuminate when plugged in. No backlight. No display even when shining a flashlight to the LCD. No 12 volt is present to or from power supply and main board. To try and eliminate power supply as the cause, I used Budm's suggestion and used a couple of 3.3k resistors to jump 5 volt to Remote/On Off and backlight on. Power supply turned on I assume because I now have 12 volts to or from main board. Backlights came on as well. So im thinking main board is the problem. Some things I've tested:
1. Fuse FP1 on main board test good and reads 5 volts without jumper
2. Fuse FP2 test good but has 0 voltage on both sides without jumper.
3. 400 volt cap on power supply:
170 volts just plugged in (not forcing power supply on)
307 volts with PS forced on. Shouldn't it be at least 380 or so?
If I disconnect everything from the power supply except AC in of course and force the PS on, the main filter cap goes crazy. Ranging up and down from as low as 220v and highest only reaching 307v. With all boards connected, It stays at a steady 307v. Thanks in advance for anyone willing to help me out on this.
1. Fuse FP1 on main board test good and reads 5 volts without jumper
2. Fuse FP2 test good but has 0 voltage on both sides without jumper.
3. 400 volt cap on power supply:
170 volts just plugged in (not forcing power supply on)
307 volts with PS forced on. Shouldn't it be at least 380 or so?
If I disconnect everything from the power supply except AC in of course and force the PS on, the main filter cap goes crazy. Ranging up and down from as low as 220v and highest only reaching 307v. With all boards connected, It stays at a steady 307v. Thanks in advance for anyone willing to help me out on this.
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