Re: Philips PUS6501 - no picture
Check the voltage ACROSS the main filter C9802. What is this voltage in standby and when the tv is turned ON.
Q8101 is for the PFC circuit. You can also check the VCC voltage across C9809 and post the voltage. Also check the voltage across C9304. It could be that C9304, C9305 or CC9313 are weak.
If the main B+ voltage is not boosted by the pfc voltage, the led voltage will also be low and likely not light the led's.
I assume 230vac line, so B+ will be 325VDC in standby but should rise to around 395vdc when the tv is on and the pfc circuit is working.
Note: the led ic U8101 (Vsen) senses the main B+ and likely will not turn on until the B+ voltage is at 395vdc.
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Re: Philips PUS6501 - no picture
I measured the voltages and when the TV is connected to the power supply, the voltages are: STBY-3.74V, 3D_ON-1.24V.
After I turn on the TV with remote voltages are: STBY-3.7V, DIM-2.55V, BL_O / F-3.08V, PS_ON-3.4V, 3D_ON-0.01V, + 12V and + 12VA- 12.2V .
The LED voltage connector is 0V and there is no picture.
When I touched the leads G and D of the Q8101 transistor with the electrodes of the voltmeter, the LED backlight came on briefly, then I touched the G and D leads a few more times and the LED backlight started flashing for about half a minute and the TV turned on and everything worked.
After that I turn off the TV for half an hour and it will not turn on again.
It remained so "on" but without a picture and after 6-7 minutes the LED backlight started flashing for about half a minute and the TV turned on and everything works again:
I turn it off again and turn it on right away and then the TV turns on and works.
I turn it off again for a few minutes and it won't turn on right away but after a few minutes the LED backlight starts flashing and the TV turns on.
As if some part needs to be heated for the TV to work, and when it cools down, the TV doesn't work or that part works a little, it doesn't work a little.
When the TV was working, the voltages on the LED connector were 45V, then 44.6V, then 40.6V on the end connectors left and right in relation to ground.
I suspect transistor Q8101 is not working properly, but I have to unsolder it and test it.
Does anyone have any idea what it might be?Attached FilesLeave a comment:
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Re: Philips PUS6501 - no picture
No blinking of the backlight, nothing? Turn the Tv on and measure each LED string with the LEDs connected and without. Make sure that all the turn on voltages are provided from the main board to the PSU, like PSon, BLon, Dimm…Leave a comment:
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Philips PUS6501 - no picture
Hello,
I have a Philips PUS6501 TV that I got as defective. The TV has no picture. I first tested the power supply and made a short circuit during the measurement on Q8101 between D and S. Therefore, the Q8102 and resistor R8101 burned out, which I changed. After that I went to test the LED backlight and one LED was burned out on each strip. Now I doubt that the LED backlight was a major malfunction and that the power supply was good.
After repairing the LED backlight, the TV did not work again. I managed to turn it on when I was measuring the voltages on the power supply with an instrument, but it turned on so that initially the LED backlight flashed for a few seconds and the TV turned on. Then everything worked, the TV could be turned on and off, everything worked. After that I unplugged it overnight and it didn't work again, it couldn't turn on.
Ambilight lights up but there is no picture.
On schematic I circled with red on page 4 which part I changed and the one I shorted.
Does anyone know what else needs to be checked or what is wrong?
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Hello, Badcaps is my last resort. I am the first owner of the monitor. I reached almost every repair store in my area, but no one even wanted to hear about troubleshooting an old CRT monitor. At this point, I have been trying to figure it out by myself, but I have no idea where to start or look for.
I wish to know how to think and locate a failing component. I will put all my efforts to learn and contribute.
- It started with a bright and greenish picture upon starting a cold monitor.
- About 2 years ago, only on the cold boot, the screen started to occasionally flash with
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I have an LG Plasma TV 60PM6700 for the past ~12 years.
In the last ~3-4 months I have been having some issues.- Problem: It started with random picture disappearing (sound still worked).
Frequency: Happened about once a week.
Solution: Had to turn off TV wait a few seconds before turning it on again. - Problem: Then it got worse and the TV started to shut down and when turning on the no picture just sound.
Frequency: Happened about once a week.
Solution: Had to turn off TV wait about 10-20 seconds and turn it on again to solve. - Problem: TV shuts down
- Problem: It started with random picture disappearing (sound still worked).
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Hello:
I have both these laptops that appeared to have the same fault so I thought I would have a go at replacing the PCH as something to learn, they both are using the same PCH.
I started on the ACER:
Up on connecting power no signs of life but current is consumed from the bench power supply and the PCH is hot.
All the caps on the top of the PCH are showing 0 ohms and the 3.3v rail is shorted.
I followed the videos from Sorin, Electronics Repair School on Youtube heating from the bottom to install. I practised on around 10 scrap... -
HI.
I have a weird problem with an old Philips 37pfl560 TV i put out of storage: the picture have a noticeable yellow hue, and its not caused by the settings (did a factory reset). I've never seen this before. I will try to get a photo with a real camera, with my phone its hard to see because of automatic white balance, but in real live the whites are really yellow.
Anyone have an idea of what can cause this? Can CCFL tubes get "warmer" with time? This tv have several analog inputs,so its nice for retrogaming.... -
I have a TCL 55P6US with sound and backlight but no picture. This model does not have a T-CON board, and the right (rear perspective) panel board is fed from the left panel board. I have not been able to induce any change by disconnecting the secondary panel board or the tape cut-off method on the primary board.
There are a bunch of voltages missing on the panel boards. I can't find any shorted caps of the panel boards, and all of the missing voltage rails read in the kiloohms, which leads me to suspect the issue may lie on the circuit board, rather than a short in the panel.
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