How to test DPS-254BP-1 RUNTKB118WJQZ power board for Sharp LC-70LE755U LC-70LE750U LC-70LE857U

[@xcross8537]

Good job 👍

[@BATMEX44]

you deserve a beer..!

[@coppelltvrepair]

Will get one...cheers!

[@stoneschanify]

Hi, thank you for this video. I have a LC70UQ17U having issues. When plugged in, I press the power button the remote to turn on the TV but no backlight or any picture/sound. Initially the blue power light is there but then it begins to blink 5 short and 2 long blinks ... do you have any idea what might be causing this? I have tried different board but still same symptoms.... Update: Ok, so I took the board out and tested it following your directions and everything seems to check out fine. At the end of the video where you tested Pin 1-2 for 12v... I only get 12v if I connect/jump pins 14,15 & 16 together. Then I test pins 1 & 2 for voltage and get the 12volts. I was hoping this was the issue because I am getting no backlights or anything on the screen instead just a short 5 and 2 blink.... i saw a video where it could also be a panel issue and the guy literally cut the plastic film that connects the LED to the driver board? Im just not sure how to dertermine which side has to be cut. Thank you again so much for this video... if you could help me further id truly appreciate it.

[@coppelltvrepair]

While not 100% certain I believe 2-5 identifies lack of one of the power voltages generated on the main board, i.e. this is a main board failure issue.

[@frankbarbaro5447]

Hello - Well done on the video - You explained it very well (Like a teacher I might add). I have one question. I have 327 Volts across the main 3 main capacitors when nothing is connected. and it jumps to 405 Volts when pins 14 and 15 are shorted. You stated it should be 160V (not 327Volts) . Is this a problem ?

[@coppelltvrepair]

It does not sound normal unless you had tested it shortly after it was working and they were still discharging.

[@frankbarbaro5447]

@@coppelltvrepair I’m in Australia. If I was local, I would come visit you to say “Hi”. I can confirm that its nominal voltage sits at 327V and when 14 and 15 are shorted it jumps to 405.volts. I get 12V on pins 1 & 2 after waking up the power board by shorting pins 15 & 16. Pin 15 has 5V standby power. Any opinions on what to do about the high 327V? If you think I have a power board problem, I’ll simply replace the board as it even has a discoloured centre above the standby circuit

[@coppelltvrepair]

@@frankbarbaro5447 Actually I was...well not wrong, but not having accounted for different countries. In Australia the AC line is 230V. Those 230V AC when rectified will give something about 230*SQRT(2) = 230*1.44 = ~330V DC, which is what you're getting. So you're good.

[@frankbarbaro5447]

@@coppelltvrepair I feel like I'm taking to the engineer who designed the circuit. You have great instant trouble shooting knowledge.. WOW well done SO it not the power supply. I have a SHARP LC-70LE951X . When I switch on the mains power I get a solid green light for around a minute then a continuous slow blink. I guess maybe something on the main board, but not the TCOM board. What do you think.

[@coppelltvrepair]

@@frankbarbaro5447 before you rule out the power board make sure it produces the 12V when tcon-on or 12von is activated. After that it becomes more complicated as we move to main board, TCon and the panel itself. Most commonly for us it would be the main board, but we've seen the others too.

[@65ondubz]

how much to fix a delta dps 285bp power supply?

[@coppelltvrepair]

www.coppelltvrepair.com/p/1873/repair-service-for-runtka985wjqz-dps-285bp-2950305604-power-supply-for-sharp-led-tvs

[@useruserovich5812]

фу какой блевотный южный акцент!