Thanks for reply, but there is no possible way to connect it wrong, it can be connected only to webcam port, but this is prevented by cable length. Other connectors are different. Its hard for me to find fault on this board, because there are no schematic anywhere and this design is complicated for me.
Everything from BL connector leads inside board, cant even find where it leads.
Maybe I can try connect that 100V capacitor + directly to + on BL connector, but I dont think it will be a good idea.
Or use step-up module from 5V or 19V rail, but it is not clean repair...
Honziq
Senior Member
Last Activity: 04-02-2025, 02:31 AM
Joined: 05-07-2014
Location: Kazaksa
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Thank for your advice.
That switches leads to this circuit.
Maybe someone messed with that when changing SSD.
This computer is designed in way you have to remove motherboard to gain access to SSD.
This four mosfets will be each for one LED string I think.
Leds in LCD are not open every string lights up with psu at 44V. But I think it's maybe open somewhere in the mobo.
I already tried all combinations of switch configuration but none of them worked.
EDIT: No that mosfets are for 3,3V and 5V rail, there are not backlight related....Leave a comment:
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Leave a comment:
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This capacitors jumps to 79V shortly after power on, then it sloooowly discharges to 19V rail voltage and then its still 19V.
Im sure it is for backlight, but I can't find a way how it is connected to BL conn. BL conn has 6pins center two is + and 2 + 2 on sides is - to separate strings with common +. But it goes to another layer of board and I can't measure where it leads....Leave a comment:
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GAPAL LA-L291p, Asus m3700wua-mb r2.1 Schématic diagram
Hello,
may I ask you for schematic diagram of motherboard:
GAPAL LA-L291p, Asus m3700wua-mb r2.1
Thanks a lot for help.... -
Leave a comment:
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Backlight problem - Asus M3200WU, board Gapal LA-L291p
Hello,
I have this All-in-one PC, after SSD change there is no picture. I was found out it is a backlight problem, but LEDs are OK. There is 4 led strings each working on 42,4V, but from board is comming only 5V.
I was repaired many backlights before but this design i will not understand.
For me it looks like it is waiting for some signal from screen to start up the backlight or something like this. Nothing seems to be damaged or shorted here.
Can someone explain me please what to do, what to check?
Thanks.... -
Thank You very much.
That mosfets I tested before, they are OK.
But I measure that voltages and on pin 1 of PQ 905 was 19V and behind PQ905 and on PL902 was 0V.
So I desoldered it and solder it back and now board is booting.
But PL902 making some weird loud whistling noises on boot. After some time it stops. And its only 9V on it.
So it looks like a problem of some capacotors around.
Or do you have suggestion why it making that loud noises?
Thanks....Leave a comment:
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[ATTACH=JSON]{"data-align":"none","data-size":"small","data-attachmentid":3255142}[/ATTACH]
Markings are CDP70 la-e141p.
I don't have quality photo, but i will send it as soon as possible.
Pin 3 goes immediately to another layer of PCB.
[URL=filedata/fetch?filedataid=334102][ATTACH=JSON]{"data-align":"none","data-size":"small","data-attachmentid":3255140}[/ATTACH][/URL]...Leave a comment:
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Hello,
I have similar problem, laptop was water damaged.
After cleaning it woks from battery/not charging, but only until battery died.
I replaced some rotten resistors, now its recognized by USB-C charger, but it's stils dead.
I got 3,3V, but not 5V ALW.
On PU901 PIN3 i got 0V. I can't find PR929 on that board.
What can cause such problem?
What program you use for opening .cad BDV files?
Thanks....Leave a comment:
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Re: Samsung 740N Inverter problem (blowning mosfets)
Now I find bad solder on one of the coils, which makes a short circuit. I placed new mosfet and monitor is running again. Now I waiting what happens after few hours
Leave a comment:
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Samsung 740N Inverter problem (blowning mosfets)
Hello,
i have samsung monitor with IP-35135B PSU.
Display does not light, i changed bad caps, pico fuse, two mosfets (I use IRF7389), then monitor starts to work.
But after few hours of using it was going black again. Mosfets are blown again.
Thanks for help
Last edited by Honziq; 09-08-2014, 11:55 PM. -
Re: Lcd screen vertical and horizontal lines
Can anyone help me? Please.Leave a comment:
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Lcd screen vertical and horizontal lines
Hello,
i have a LCD monitor/TV sencor SLT2222DVBT. After turning on screen shows vertical lines that fades out after minute and few permanent horizontal lines.
First image is taken after turning on. Last two is taken after few seconds of turning on.
[ATTACH]90836[/ATTACH]
[ATTACH]90837[/ATTACH]
[ATTACH]90835[/ATTACH]
Edit:
Here is some videos:
[url]http://youtu.be/kGnS8L9h9sk[/url]
[url]http://youtu.be/etzsRS5K394[/url]Hello,
i have a LCD monitor/TV sencor SLT2222DVBT. After turning on screen shows vertical...Last edited by Honziq; 07-23-2014, 12:23 PM. -
Re: YP1922-4L LCD power board repair
Thanks,
i try to swap tubes with one laptop screen tube.
One of the top tubes is bad. When laptop screen is connected TV running always.
Thanks a lot.Leave a comment:
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Re: YP1922-4L LCD power board repair
Hello,
I am in Czech Republic, mains voltage is 220V....Leave a comment:
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Re: YP1922-4L LCD power board repair
S1 to S2 - 1080 Ohm
S2 to S3 - 1092 Ohm...Leave a comment:
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YP1922-4L LCD power board repair
I have LG LCD TV. When I turn on the TV backlight turns on for 1 sec and then goes back off. I think it is bad invertor. But i dont know, which of components is bat. MOSFETs and caps seems OK.
Help me, please.
Thanks.[ATTACH]90268[/ATTACH]
[ATTACH]90269[/ATTACH]I have LG LCD TV. When I turn on the TV backlight turns on for 1 sec and then goes back off. I think it is bad invertor. But i dont know, which of components is bat. MOSFETs and caps seems OK.
Help me, please.
Thanks.[ATTACH]90268[/ATTACH]
[ATTACH]90269[/ATTACH]... -
Re: HP 620 does not turn on
Thanks, and do you have schematic? Please. I cant find it....Leave a comment:
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Re: HP 620 does not turn on
Thanks, i buy new one and try it....Leave a comment:
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