Re: AOC LV243XIP 23.8 inch Monitor Screen Flickering
Hello momaka,
thank you for your further help,
yes VCC18 have stable voltage 1.8V and resistance 0.268V on continuity mode, and yes after changing L2 VGH have stable 29V and VGL have -7.7V stable, sorry for i forgot to mention VGL_UO in my last post, yes VGL_UO have resistance 0.55V on continuity mode and have voltage -14/-13 but keep keep up and down -14V/13V and not stable,
you mean that white circle on right side? that is room ceiling light shadow, LCD is ok, just have small white line...
Ali101
Senior Member
Last Activity: 05-13-2022, 07:05 PM
Joined: 07-25-2017
Location: Taipei
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Re: AOC LV243XIP 23.8 inch Monitor Screen Flickering
Hi momaka,
I had follow your instructions and below results i got,
VGH test point have 29V and it drop to 4.2V within few seconds, L2 had 0 resistance, it had 11.8V at start on both side and drop to 4.7V within few seconds, i replaced your advised all caps and nothing changed hence i believe all these caps seems ok,
R216: 2.8,
R219: 250K,
R220: 250K,
test point vcc18 have 1.8v and it gone within few seconds, test point 3.3V have stable 3.3V
I replaced L2, i takeout similar SMD inductor...Last edited by Ali101; 03-17-2022, 06:17 AM.Leave a comment:
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Re: AOC LV243XIP 23.8 inch Monitor Screen Flickering
Hello momaka,
Thank you for your kids help,
let me quickly check and get back to you,
Thanks.Leave a comment:
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Re: AOC LV243XIP 23.8 inch Monitor Screen Flickering
Hi momaka,
Thank you for further help,
fuse (F1) have stable voltage, 5V, but VDD main having issue, when LCD power on and image show ok for few seconds voltages are 11V but after few seconds once image faded voltage goes drop to 4.7V and keep stay at 4.7V, i had checked all T-con ceramic caps and none shoes shot in continuity mode, the chip next to SMT inductor is getting little bit hot but not alot,
dual diodes D2, D3, and D4 only D2 have voltages 11V for few seconds and it also drop to 4.7V and keep stay...Leave a comment:
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Re: AOC LV243XIP 23.8 inch Monitor Screen Flickering
Hi momaka, thanks for above suggestion and help, highly appreciated, have you saw this video which i post on youtube [url]https://youtu.be/z9hIq7UjjIo[/url]
This monitor backlight is ok, what problem it do is one connect via hdmi or vga it give picture for few seconds and then image get freeze and disappear slowly and backlight keep stay there, so if I unplug power and put back power cable image come back again for few seconds and gone in same way, as you suggest above i had used hot air temperature 360c...Leave a comment:
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AOC LV243XIP 23.8 inch Monitor Screen Flickering
Hello,
AOC LV243XIP 23.8 inch Monitor screen flickering after power on monitor within few seconds and image disappear, if power off and on again then then image come back and again disappear within few seconds, i had checked all capacitor which seems ok to me, i have doubt something wrong with LCD board and mainboard is ok, i don't have other same monitor so i check and verify either LCD have issue or mainboard,
shall highly appreciated any hep to fix this monitor,
PS. i had attached pics and short video for reference,
Video Youtube Link: [url]https://youtu.be/z9hIq7UjjIo[/url]... -
Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
from Aliexpress
[url]https://www.aliexpress.com/item/726323451.html?spm=2114.01020208.3.68.fzIeyE&ws_ab_test=searchweb201556_6_79_78_77_82_80_62,searchweb201644_0,searchweb201560_4[/url]
but as i know soldering stuff and have right equipment so i order only LCD Glass but it will be better for you to buy hole penal if you don't have right equipment and knowledge. just search on above website 8 segment Digital LCD Module and you will get bunch of results.Re: DC Power Supply (DF1730SB-5A) ProgrammableLeave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
still waiting for LCD delivered from China, shall post back here once received new LCD,
Thanks Sam.Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
@R_J no difference with clean sockets and board, all same, all segments on,
@eccerror i had replaced new IC 7106 but it not fixed issue, hence it is LCD fault, buying new LCD and shall replace,
Thanks.Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
@R_J no i not did, let me try this before placing LCD order online,
Thanks for suggestion, appreciated,Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
@sam @eccerr0r thanks alot for professional suggestions and kind help, appreciated, shall follow them on same,
Shall return with feedback once done,
Thanks.Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
segments keep on even disconnect all connections of Power supply from display board & just give 9V external to display board,
ONE LCD is around USD $2 but i need to buy them from China Online (Aliexpress) & it will take huge time to arrive,
so can't be quick results,
have any suggestion to try before remove LCDs?Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
i believe all problem is LCD,
found one post on French site
[url]https://www.jelora.fr/post/2017/09/24/Teardown-Demontage-Reparation-alimentation-de-laboratoire-HQ-Power-PS1503SB.html[/url]
need to use google translate in chrome to understand,
this guy have similar problem, LCD display shows all segments and he replace LCD and his problem solved,
here also one guy discussing same issue with same power supply modle
[url]http://forum.ixbt.com/topic.cgi?id=48:11747[/url]Re:...Last edited by Ali101; 02-19-2020, 12:14 AM.Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
i have Desoldiering Gun and hot air station, shall follow your instructions while remove LCD,
Thanks samLeave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
@R_J thank for hint, really helpful
@sam i had replace new Meter IC Chip on both display boards and nothing works, all same error it showing, i remove PIN number ( # 37 ) from IC and still same,
i not removed LCD screen yet from board since it soldered, inside IC section is same how R_J show on Post #34 ,
possible my both LCD have some problem?
@eccerr0r i not remove LCD yet but my next step will be remove LCD and see if have anything backside of board,
if need any further test,...Last edited by Ali101; 02-18-2020, 07:01 PM.Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
Noted, will buy new IC and replace,
shall get back with results once done,
Thanks.Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
IC is soldered inside of display board, mean in order to remove solder of IC i have to first remove LCD from board,
i had given 9V external & removed main board inputs but this not works, meter not given 00.00 Volts and it show still same
so should i buy two new ICs and just replace them?
Awaiting your further professional suggestions,
P.S sorry for late reply, all the day i am on work and on night i have time to test your instructions...Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
@R_J & sam, Thanks.
@sam let me follow your instructions one by one & get back with results,Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
@R_J no that 12V line come from Main board AQF7.820.7120 ,
enclosed both board back side pics, i hook 12V external on AQF7.820.7173 and then it transfer 9V to LCD board and LCD IC show 9V also on pin-1 & pin-26 but it still show same error on LCD and seems this issue is not related to 9V, issue might be some where else,
@sam Pin 37 have nothing connected, look at attached pic...Leave a comment:
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Re: DC Power Supply (DF1730SB-5A) Programmable LCD Reading Problem
both diodes V3 & V4 given same voltages, 7.8V to 8VLeave a comment:
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