Re: Issue with DVD-RW drive, needs calibration?
LOL that's what i thought i mean, those websites never explained in detail the reason why you should move the potentiometers to 600 and 700 ohms they just said "that's the number you need to fix it".
Youtube has many videos with people doing this 600-700 ohms technique even with Xbox and Playstation consoles, anyway yeah np i already bought two drives i just had this one getting dust, btw i tried to restore the original values but lol it's hard those screws are very sensitive so i just managed to get 187 ohms...
TacoLoco
Member
Last Activity: 07-29-2019, 05:23 PM
Joined: 05-04-2019
Location: cdmx
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Issue with DVD-RW drive, needs calibration?
Hello!
I have this old 2014 LG, CD DVD-RW Sata drive that stopped reading certain discs, i don't know why or how but suddenly the drive wouldn't recognize any Polaroid dvd-r discs i previously burned with nero or imgburn software.
The weird thing is that this LG drive can successfully record data in those polaroid dvd's but it can't read them afterwards like if the burning process was a failure but it wasn't, the drive did his job because i could read the discs data anywhere else (other computers, blu-ray players)
Then i tried with Sony dvd's, it was... -
Re: Benq G2420HD wire identification/assignment & LED conversion
Wow thats awesome i wish i knew how to properly repair stuff like that coz i would do the same lol, get some "broken" monitors, repair and enjoy.
Oh and the glass isn't cracked, that's the way how it is coz every single flex circuit section has the same "crack" when it reaches the glass, well thats what it seems to me.
I just turned on the computer and found just one green line, i pushed once again with a needle (not the pointy side) till i found...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
I was looking for new monitors the last 2 weeks and this is much worse than i thought because there are so many and i can't make up my mind about picking one cheap budget 24" 1080p monitor and those who got my attention have only 60-70% positive reviews coz some people complained about things like: dead pixels, ghosting, poor sharpness, contrast and more... anyway that's not the reason why im posting after 1 month...
[B]I FOUND THE PROBLEM[/B] and it was exactly what you told...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
well i've tried for the last 2 hours and the line won't disappear.
I literally touched, put pressure, shake, pressed and more with little to almost no force and then i did it with much more "violence" but nothing happened, i did this with all the perimeter of the screen, with my fingers and a plastic spatula.
I touched the screen, the blue glue, the tab-bonds, the flex cables/circuit, i moved them, let them hang with no screws, pushed them in different ways and still nothing...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
I'll try once i finish this hillbilly modification im doing with the plastic and aluminium frames, disassembling both was incredibly difficult so i'm cutting retention clips and other stuff to make it much easier when assembling, seriously these things are made to never be dismantled and when you try omg it's like doing some major surgery.
imma push every single tiny pin with some plastic tool and check carefully if the line fades away, moves or anything like that, thx for the a...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
Getting this result after all this work is kinda depressing but this monitor has been working for many years almost every day so it's not that bad i mean it's a lot of time without a single malfunction.
Yesterday i removed the power to the inverter zone and more jumper wires, almost like insulating the transformers zone entirely and the screen still works (with the dumb line ofc) also i pushed the tab bonds (with the power on) and even the screen a little harder to see if the line or anything else...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
A little update about this dumb white vertical band/line...
1- I disconnected the "LED kit" and the white line still there.
2- Re-soldered/connected the old black and brown wires to the power board and logic board and the line is there.
3- Reversed the entire "LED conversion" process restoring the jumper wires, giving voltage back to the Inverter circuit like if i never touched the boards, i got all the old voltages on caps (17v and 5v) and 3.3v for...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
Well something went wrong...
There's a white vertical line and i have absolutely no clue why this happened, maybe the FLEX/flat cables were dirty with finger prints or something, one goes to the monitor buttons and then we have a big one that goes to LCD screen.
I was extra careful with the screen, actually i didn't touch it for one month so i don't think i damaged the lcd screen board, i'd guess i have to disassemble again and clean the flat cables pins with isopropyl...Leave a comment:
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Re: Bios password removal for Lenovo A475
I think you just need to remove the 3v cr2032 battery for 10 minutes or something.
But that requires some disassembly so you better google the service manual or some disassembly video for the lenovo.Leave a comment:
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Re: Does flux expire ?? Flux discussion.
yeah, roosmann flux always stays there no matter what and sometimes he even puts more flux and you can see the circuits and stuff drowning in flux that behaves like gel, water or something.
I can't get amtech flux at decent price in my country and the cheap ones dry out soon as you put the iron in the pad, almost immediately, leaving sticky residue, i wish i could get my hands in some of that nice stuff that louis has....Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
It's working!!!!
sorta i mean, havent test the lcd screen yet but the LED's are working and it has a strong brightness.
- I just did what you guys told me to do, VIN to capacitor C701, GND to the same capacitor (negative) and both DIM and ENA to the logic board replacing the brown and black wire, it turns on, leds are working and well i'll see if DIM works with the lcd screen interface but that's something for tomorrow.
- Also i removed jumper wires JW16 and...Last edited by TacoLoco; 05-19-2019, 06:52 AM.Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
So we identified the ENA and PWN signals, now I just need to remove some jumper wires and solder the LED driver VIN and GND cables, seems like I’m ready to start with this project, i'll do it tonight BUT I’m going ask some questions about the procedure and stuff for everyone else and myself.
I uploaded a pic showing how im gonna do it, the only difference between the info i got would be connecting the VIN to the fuse (stj) or somewhere near the JW5 (R_J)
...Last edited by TacoLoco; 05-16-2019, 07:46 AM.Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
awesome i didn't know that.
The fuse shares the same PCB path with the positive pin of 25v220uf (17v power on) cap, then it goes to other line with all the 35v470uF caps positive pins (17v) is that what people calls "a power line/path"?
So if the yellow fuse is my power for the CA-155 led driver, how do i connect/solder the wire there? right into one of the fuse legs/solder joints (which one?) do i need to read values with my multimeter? if that's so please tell me which mode i need...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
The ic801 ccfl driver chip is the [B]OZ9933[/B]ic
Here is the monitor manual with schematics and the data sheet for OZ9933 circuit.
[url]https://cdn.badcaps-static.com/pdfs/ad77a4e038d9005d3f749182ddbcd421.pdf[/url]
page 5
So the jw11 and jw10 are the dim and ena? it makes sense since those jumper wires lead directly to brown and black both with 3.3v
About the yellow fuse i can't find it, is the thing that looks like a yellow ceramic cap labeled...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
UPDATE 3:
Ok i think this is pretty much all i can do without going deep into electronics....
I checked all the capacitors on the board here's the result:
[COLOR="Green"]plugged/POWER ON[/COLOR]
5 caps with 35v470uF = 17v
1 cap with 25v470uF = 5v
1 cap with 25v470uF = 17v
1 cap with 50v47uF = 5v
Without further advice i think brown and black wires on the powerboard are the DIM and ENA, im gonna disconnect those cables,...Last edited by TacoLoco; 05-14-2019, 03:57 PM.Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
Uh ok i can't find the option to edit previous posts, anyway...
UPDATE 2:
[B]Direct Current Voltage - 20v range, same results on both Logic and power supply board[/B]
Plugged and [B][COLOR="SeaGreen"]power-on.[/COLOR] [/B]
Black = 3.35v
Brown = 3.36v
Red = 0.00v
Orange = 0.00v
Yellow = 5.00v
Green = 5.00v
Plugged and [COLOR="Red"]power-off[/COLOR]
Black = 0.00v
...Leave a comment:
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Re: Benq G2420HD wire identification/assignment & LED conversion
[B]UPDATE:[/B]
I measured/tested the pins with the diode mode (the one that "beeps") having power-off & unplugged, no current whatsoever and:
1st and 2nd (black and brown) = nothing, no sound and nothing on multimeter
3rd and 4th (red and orange) = it gives sound/signal.
5th and 6th (yellow and green) = it gives just one short "beep" and some numbers on the multimeter between 600-700 and 1500, i dont whats the meaning of this....Leave a comment:
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Benq G2420HD wire identification/assignment & LED conversion
Long story short... ccfl's failed, bought this "ca-155" led replacement but can't identify pin/wire assignment on both power supply board and logic board since neither have anything printed over the pcb, no ENA, DIM, VCC, GND, 5v, BL-ADJ or anything like that, nothing!!!
Hello everyone and let me start with two warnings to help you understand the text wall ahead :p
first, my english is absolutely bad, mediocre at best so i apologize in advance for making your eyes bleed, you may think [I]"then what are you doing here and not searching the help you need in... -
Re: New Members - please post your introductions here
hello everyone!
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