In US the Line voltage is 120 vac and the cap charges to 1.414 times the input so the the volyage off the Bridge Rectifier should be 120 x 1.414 = 169.68 or 170 vac but I measured 397 vdc. is this because the Boost Converter PFC circuitry? Fuse was no blown open. The customer dis not want the set but it left me wondering what would cause this and how to repair it in another set If I ever see this problem again. What the best way to troubleshoot a PFC circuit?
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Re: Vizio VW26L has 397vdc on main cap ?
Yes, that is correct, the PFC Voltage booster will boost the DC to about 380~400VDC. It also means the PFC Voltage booster is working, when the TV is in standby, the voltage on the main filter cap will be around 170VDC, when PS-ON is applied to the power supply board, the PFC will turn on, the other main power supply (12V/24V) will also turn on. That is also why the main cap is rated at 450VDC instead of 250vdc.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
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I suppose the real question is whether the existing pinouts from ether a 17IPS71 psu are cross compatible with a 17IPS12 psu? If they are then the exchange of the main boards should have no issues providing the screen is compatible with both main boards. Obviously you can change the screen configurations easily enough (providing you have the correct files) for the main board. Why may you ask would I do this? Well a lot of the smart features are no longer working on a Hitachi 48HBT62U main board I wish to give it a new lease of life!
Obviously the same LVDS connector for the screen connection... -
Hi and thanks in advance for any input you might provide!
I have a Sceptre U550CV-UMRD8POTV83BB 4K LED (this is a dumb tv) that I bought new in August 2021, so It's just completed 3 years.
Main power board model: TP.MS3683.PC821 T-Con board: N4TP546UHDPU2L_BO
Last Sunday I was watching a dvd and fell asleep for about half hour, when I awoke the tv screen was black and couldn't get the dvd menu to show, so I changed the input to antenna and had sound but no picture, turned it off. I then got online and found this great site! ....read many troubleshooting tips and this... -
Hello, i am working on Vizio M70-C3. It can hardly power on, it takes 15 power button presses or remote. Seems like eeprom problem that I seen before but all reading online says that this tv has power board or main board problem.
When tv powers on vizio V logo shows nice on whole screen. picture 1
When it goes into tv mode it only shows good picture on left side of screen, right is all scrabbled up. pic 2
When i start youtube picture shows on left side fine, right is all scrambled. pic 2
When i click video to start playing picture goes black(like when you change... -
Hi. Anyone who has experience with these vizio sets, which pin on this connector is the standby, the 5V pin? Trying to rule out the PSU before ordering a mainboard. I'm getting 0 Volts on all pins on this connector. Trying to jump the standby and PS ON pins to see if the PSU is functioning. Thanks in advance. -
Hi.
picked up another TV. This time is a Vizio M65-C1. TV does not turn on. I had repaired another 60 inch vizio , Bad main board.
When power button is pressed, the Power led indicator on the bottom right, turns for a few seconds and then it fades away. No backlight or Vizio logo on screen. Removed back cover and repeated test.
This is the TV This TV is a little different from the Samsung I have worked on. Power supply is on the Left side, Main Bd is on the right side, T-CON , not in the picture is on the bottom. I am assuming that the boards in the middle are the LED...
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