We will start with this question. This tv clicks but does not start-up. shuts down after about 4 sec. There is no voltage at vset.
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Re: Sanyo DP42545
You will get a lot more help by at least up load good clear pictures of the whole backside of the TV showing all the boards and pictures of the whole board of each board.Last edited by budm; 02-18-2018, 07:54 PM.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 -
Re: Sanyo DP42545
Pictures of tv.Attached FilesComment
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Re: Sanyo DP42545
Can anyone tell me if the vset voltage is generated from the power supply.Comment
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Re: Sanyo DP42545
Which board is Vset test point on, and is there a Vset adjustment pot on power board?Comment
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Re: Sanyo DP42545
Vset is on main power board and feeds VS yes there is an adjustment for that on main.Comment
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Re: Sanyo DP42545
Vset is also listed on VS board.Comment
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Re: Sanyo DP42545
Here is the vset trim pot. Also, are you getting a ps_on signal from the main?
edit: re-read your post, see you found the adjustment pot.Attached FilesLast edited by will62; 02-19-2018, 11:21 PM.Comment
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Re: Sanyo DP42545
The following is a list of Measured voltages.
Va= 70.3
Vsc= -198
Vs= 210
Ve= 82
Vset= -198 than goes away sticker says +198 led on board flashes 6 times Vset?
stby= 5.18
pson board says (vs on) 0 plugged in rises to 3.26 when on-off switch pressedAttached FilesComment
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Re: Sanyo DP42545
I'm adding a diagram that may help you troubleshoot the Vset voltage.Attached FilesComment
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Re: Sanyo DP42545
What kind of load for testing purposes could i use.Comment
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Re: Sanyo DP42545
I had changed the power supply board and it seems unlikely the replacement board would have the same problem, but it does give the same symptoms. Perhaps a dummy load would prove that out if possible.Comment
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Re: Sanyo DP42545
Not sure what you could use to load test the Vset line. I believe it is only rated to 50mA, so that would be a little less than 10 watts. If you have already replaced the power board, I would move on to the Y-main board and trace the Vset circuit there.
You said that when you first apply power, Vset reads -198V, then goes to 0. That -198V is the Vscan voltage. Maybe you could check the resistance from Vset to Vscan with cn8003 connected and disconnected. Try the same for Vset to ground.Comment
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Re: Sanyo DP42545
Thank You for your help thus far. Will check the resistance and see where that leads.Comment
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Re: Sanyo DP42545
Update on DP42545. A friend of mine has the exact same tv only working, and i was able to sub some boards to determine where my issue was. Well it did turn out to be the power supply board. The bad part is i find no one that has this board available. The parts suggested to check could not be in a much worse place to get at. Do you think i can remove these parts with just a soldering iron. Afraid with all the sub components on the underside of board heat gun would be too much, any suggestions. Thanks in advance.Comment
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Re: Sanyo DP42545
They're all through hole, so should be OK with an iron. Before you remove them, I'd try to get part numbers off them, and look up data sheets to see what you can test in circuit. You may get lucky and find the bad component w/o removing them all. If you look from the top of the board, you'll see that the Vscan and Ve circuits are using the same components (confirm visually). So, you should be able to compare the suspect parts on the Vset circuit with known good parts in the other 2 circuits.Comment
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Hi i have an issue with LG 42lw4500 wich after pressing the power button flashes red then goes solid white light 2 clicks and nothing , the weird thing is SOMETIMES if i leave the tv plugged in it would come on and fuction normally (i should mention that vertical rectangle going from the bottom to the top of the screen have some red dot artafacts it only appear in somthing like the tv input menu and any input i give like vga , but not in the system menu , i thought i should mention this , i cannot confirme if the tv had this issue when it was up and running in its previous owner . ) when checking... -
Hi it looks like everything works don't know where to test except the 390v in the 2 capacitor in the hot side of the power supply and the weird 180v in the diodes in the cold side that should be discharged it is writin on the circuit no more you can read what is written on the circuit quite srrange color mixiing yellow and white
anyhow i couldn't t read anything else
the backlight is on strong and the screen does not get dark or very dark but no pictures
the mainborad feels a bit hott on the black part i test it to 52 degree's against 34 to 40 on the rest of it
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The 55" LG has been in the basement for a few months without being used. Turned it on yesterday, set came on as it should and showed a complete screen for about 5 seconds (was on a broadcast channel but no antenna was connected), then the screen went mostly dark with about 1/3 of the screen on the right lighting up with brighter lines in that lit part (sorry, no pictures of that). Power LED was cycling too, preventing the TV from fully powering up.
Pulled the back off, all boards looked OK. Pulled the LED connector, turned the set on to see if it would power up but I don't belive it... -
Hey all
I've been working on a 1984 Sanyo 27" color TV which had a smattering of bad caps in the video switching circuit. I found this oddball little 1uF 25V cap which looks to me like an early polymer, but I can't find concrete info proving it. I know Sanyo was a big player in early polymer cap development and this is the time period where they were just getting on the market, so I'm wondering if anyone has crusty old datasheets that could help identify it and determine if my suspicions are right? It has the same epoxy end seal and font/formatting as some old stock Os-Cons I've got laying...
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Hey, I find it very absurd that the SVOD4 costs so much and has zero documentation. I had no other choice than to buy it to unlock ECs, if there was any documentation or firmware avalible I could've made it or something simmilar. Anyways here are some of the most important parts:
STM32H723VGT6 MCU - It's a microcontroller by STMicroelectronics and its the whole brain of the SVOD4. It has flash memory for the firmware which can be updated by the SVOD4 program. Its also powered by the AMS117 which converts 5v into 3.3V. 7€ on AliExpress.
GW1N-UV9UG169C6/I5 FPGA - Its a...07-04-2025, 12:23 PM
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