ThinkPad T490 20N2000CSC NM-B901 no signs of life - short on 5V SMPS, ThinkEngine-3 hot - *speculations*

[feliks912]

Attached schematic 🙂.

Laptop gives no signs of life. No fan and no CPU heat.

Think Engine BD4179MWV is hot on plugging in *AND* pressing the power button.

Discovered short to ground on VCC5M power delivery IC NB690GRP (5 volt line, not the high current VCC5M_PD). I'm puzzled.

Nothing else warm on board. CPU resistances OK, 9V VSYS line present. All misc disconnected.

If the think engine shorted to ground first, how could have it caused the 5v low side FET to fault by shorting to ground? Those things rarely if ever happen on current...

[ub6ib969]

Hi,

working on a ASUS ROG STRIX GL702VSK 60NB0DZ0-MB1260 that does not power on. At the PQ8900 PIN2 (P_CHG_ACMOS_G_20) I am receiving 24.7V and PIN1 (P_CHG_ACMOS_S_20) 20V, however when I place the PQ8901 P_CHG_ACMOS_G_20 it drops 0V. I don't have the replacement mosfets ( N-MOSFET QM3058M6AC PRPAK5*6
UBIQ) however will any N-channel mosfet with similar parameters work ? I also found that PCI8703, PCI8701 are shorted. any help would be grateful.

[estabilito]

Hello, i bought dead nintendo switch oled.
after plugging charger with amp meter device shows 5v and 0,0 or 0,02 amperage draw.
I inspected motherboard and someone tried to reflow or replace m92t36 and didn't do it well, i resoldered it proper and find that usb-c fuse was blown too(replaced it).
After this device started to draw 15v and something around 0,48 but only for few seconds after this returned to 0A draw.
I tried to plug motherboard without battery - shows 15 0A and when charger was pluged i put battery back in then console started to charging battery but stuck...

[bigboots]

Hi all
Would like some help to identify this ic please. I cannot find a schematics for the board.
Thanks in advance.

[LEEDASH]

Hello all, Aiwa TX-110 Tuner got out of storage and the buttons was held in by some gloop, What glue would you use to restick these buttons (they are no snapped off)

Thank you

[CraigR]

I have a 12v psu from a DJ lighting system and I can not seem to figure this one out. The board so far had a blown fuse and a shorted voltage regulator. After replacing those I get 12v out but hooking a load to it the voltage seems to bounce between 5v and 0v. I remove all the caps and checked those and replaced 2 that were only questionable. I know it's not the device I connect it to as I put 12v to it with my bench power source and it works fine....

[almarhum]

Has one here really gone through fixing laptop screen vertical line(s) by repairing/replacing its Embedded DisplayPort (EDP) cable, so would recount and share the complete steps of the process here now?

As most, if not all, believe the laptop screen vertical line(s) caused by defective Embedded DisplayPort (EDP) cable which slipped and passed through either laptop screen hinge but post here is asking help to elaborate definitively the useful, real knowledge of repairing in the most complete, correct way, esp. can decide/determine whether the cable can still be fixed or must be re...

[nabilgo]

hi

need bios for toshiba portege r30-a part no pt343u borad number FASRSY1 A3688A

the old bios stat but no data...

[teruger]

Hello guys

My laptop have a FAN issue, i tried with a new FAN but the issue persist.
The motherboar is LA-G714P

I measured the JFAN1 connector

pin 1: 5v
pin 2: 0v FAN1_PWM
pin 3: 3v FAN1_TACH (this pin should not be 0v if the fan is off??)
pin 4: GND

Tanks for advance!

[moscast]

Hi everyone, I have the same problem with two Dell notebooks. One has the EDC41 LA-G891P motherboard and the other has the EDC50 LA-901P motherboard. Both do not turn on and the processor also heats up a little.
In the coils there are 3.3v - 5.1v - 13v - 19v - 1.8 - 1.05V and 1.0V prime core
On both notebooks, if I press the power button the LED turns red and if I release the button the LED turns off.
What could I still check before saying the processor is dead?
Thank you

[mferna14]

I am working on ACER Aspire A515-54-74LM Serial # NXHNAAA00693913C647600 (SNID: 93908099676 ). Motherboard DA0ZAWMB8G0 Rev.G (UMA, no video chip on this board). It turns on fine but when booting to Windows 11, it just keep loading. The Windows ring is continously spinning & does not proceed anywhere. I tried with another known good SSD Card with 100% Windows 11 bootable from this SSD., & result if still the same. BIOS ME Region has been cleaned, same result with old & new BIOS bin files. No Liquid spill anywhere on the main motherboard or the SSD Connector. What is the next step I...

[osbln]

Hello,


i am searching for schematics and boardview for NM-E791

unfortunately I could not find anything here in the forum

Thank You

[Techboxcomputer]

This has happened on three keyboards, so now I am assuming it is something in the machine but I can't track it down. Every time you plug in a logitech wireless keyboard it will immediately switch the "c" and the "v" permanent on these boards. There is no malicious software I can find, the board cannot be reset or put back. The very last one I tried was a MK 235 with the same end result. If you plug in a Microsoft wired comfort curve board, no problem at all. I have tried cleaning the system, deleting all boards from the device manager, updating the Logi software,checking MS...

[the Benninger]

dont work, only 3 asterics on lcd

It seems like a BIOS problem in the support of the page they have to update from Windows, but this is not even recognized as a device on the computer, I am looking for help I think you can rewrite the NAND memory again but I don't have the accessory

If anyone with a sililar case or experience has something to comment on, it is welcome

[ATTACH=JSON]{"data-align":"none","data-size":"medium","data-attachmentid":3266527}[/ATTACH]

Unfortunately they provide a *.fls...

[niconetor]

Hi! I have a corrumpt bios for this laptop

Model: Toshiba Satellite L50-A-14K
Motherboard: tmt YA-4A1 E114139 Rev 2.1
H000057570

No power, only led charging

This laptop have got two winbond
25q32fvsiq and 25q16dvsig

Thanks for all reply!

[salah11]

hello,
need bios dump for asus fx570u
attached the original bios,
the computer run and enter bios, but not windows boot
and the problem is that all the bios parameters are jamed
thank you...

[Squaryhead]

Hi,
I'm struggling to find a software to reconfigure a GD 25LB128 chip with a CH341 A.
Do you know any ?
Thanks !

[grimacelord]

This laptop is the same laptop I was working on [URL="https://www.badcaps.net/forum/troubleshooting-hardware-devices-and-electronics-theory/troubleshooting-laptops-tablets-and-mobile-devices/bios-requests-only/3262622-hp-14-dq0055dx-bios-problem-pending-image-being-cleared-loop"]in this thread[/URL] and I wasn't sure if I should post a new topic or post in that thread because I already solved the issue that thread was discussing and this is a completely different issue although it is dealing with the same laptop. I decided to make a new thread since it's a new issue, but please move...

[amirheidari681]

Hi my friend,
I have ASUS r1605za and it's keyboard worked out after about 10 min.
I think the problem is related to bios.
can any body help me and correct my backup file?
( I have the same problem on another ASUS laptop and I fix it with correct bios file.)
sn: NBN0CV043681455...

[krsta]

Hi guys, hope someone could direct me in right way.

So i got the ASUS ROG THOR 1200W PLATINUM for 15€.

The first time i plugged it in wall socket there was no 5VSB present, so i disassembled it took a little peak inside and left it on shelf for a day.
Next day the 5VSB was present and the psu worked the whole day (outside of computer, shorting PS_ON to ground).
I tested it for a few days like than and then installed in my computer, it worked flawlessley for 1 month.(gaming and such for a few hours).

Few days ago i left it torrenting and saw...

[vpower]

Hi, I have this laptop, it is completely dead, no charging light when connected to a working charger.
Can anyone help me with some hints for troubleshooting this laptop?
Thanks in advance...

[appie1206]

Hello there friends

Can someone Clear this bios file for me ?
serialnumber: 5CG33778XV
productid: 709Z1AV

Thanks in advance...

[NiroPall]

Hello friends,
Please share this schematic if you have,
EPK50 LA-G07EP REV: 2.0 (HP)

Thank you.

[ImpossibleRepairs]

Hi Good peoples;

Been working on a turtle beach Velocity one flight controller; The slide pot for the throttle (black) isn't calibrating properly, it will register the axis with some wriggle until pressure is released;

Does anyone know the specifics for these Potentiometers?? I have attached photos;

Board number is LBX-19500，
C-V1.1 202011

please and thanks as always

[Comp_Pro]

Hello all,

Am trying to figure out this backlight issue with this A1990 Macbook Pro.

Tests performed:

There is no backlight even with a good screen.
Backlight IC is receiving the correct support voltages.
Fuse F8400 ok
Current sense resistor R8400 ok
Backlight IC is receiving 3.3V on enable pin.
Backlight IC receiving voltage from PPBUS_G3H, aprox 12.5V.
Backlight IC receiving 5V from PP5V_G3S
Backlight IC BKLT_SCL and BKLT_SDA both measure 0.545V diode mode to ground
I2C_BKLT_SCL and I2C_BKLT_SDA both measure...

[fixxz]

Could you help me get the bios for this lenovo the card model is JS47A/JS57A/JS77A NM-E531 REV 1.0 I do not have the original file since the chip was damaged

[gjgib]

Hello, this might be embarassing since I consider it a dumb question but keeps me kinda stuck sometimes in my journey.

I want to know if there is any post in this forum which explains my questions. [B]A)[/B] [B]When, where and how do I know when X voltage line is input or output. Example: [/B]

[URL=filedata/fetch?id=3266119&d=1715040463][ATTACH=JSON]{"alt":"Click image for larger version Name:\timage.png Views:\t0 Size:\t151.9 KB ID:\t3266119","data-align":"none","data-attachmentid":"3266119","data-size":"thumb"}[/ATTACH][/URL]...

[techrefurbca]

Hi,

It is my first BIOS request here.
I have a bios-locked AUS M415D

ASUS X415DAP

[kk126]

Hello, I have a da0h9bmbcd0 card which had a liquid spill, there was an area in which corrosion damaged the power rails but it is almost undetectable to where they are connected, I looked for the schematic diagram of the equipment but it is not available so if you can help me I would appreciate help knowing which integrated part is the one that had the damage....

[PITERPENY]

there is no reaction, it hangs at 20 V/0A. There was a little corrosion in the u7650 area. Replacing the u7000 did not help. Tell me, what else could it be? PPBUS_G3H=12.9V
Flashing the bios with a clean region also did not work!

[atmega4]

please i need unlock BIOS unowhy Y13 2021
Production year : Aout 2021
Model : Y13G011S4EI
Motherboard : EM_IG116_200b_ene_F_V1.0...

[Mogli1476]

Hey @all,

my ipad Pro dont want to work anymore. I measured the incoming amps which is approx. 0.5A. Then I changed the Tristar IC and blow out some parts near this IC. Now I want to find the missing parts. Thats why i´m asking for the schematics & board view for this ipad pro.

Thank for your help!

Best regards, Mike

[spleenharvester]

I bought a T12-958 recently with an M8 handle and until now it has worked very well. The tip wasn't earthed but that was easily resolved.

Now, whenever it is switched on, it heats up to about 70*C then shows an [INVER] error on the screen and stops. In order to fix it I have to either unplug and re-plug the handle, or unplug and re-insert the tip from the handle. While doing that it changes to [ERROR], then it finishes heating up and works perfectly. Until it's turned off, after which it will show [INVER] again next time it is turned on.

Any idea what the problem is?

[babydoll8867]

Hi, i have a Dell 3681 SFF, with its original bios the led blinks 3,6 (some bios error). i tried with a clear me version from another site and it was ok, it gave image but entered manufacturing mode. tried entering service tag but it can't be saved and i can't exit manufacturing mode. can anyone help me with a fix for my original bios file? i attach it here, ST: 3FQ2SF3...

[EazyBone]

Shown in picture, trying to replace a MOSFET and looks like I knocked this off, in guessing it's the same as one next to it. Has 1.8 Mohms. Any way to bypass it? It's on the hot side

The component circled is the one there, the arrow is I think another of same component?

[fredyjbi]

Please help sir, this board does not turn on because VSYS_OUT is 9.2v, I compared it with a normal board VSYS_OUT is 10.2v, I have replaced the PQ101 and PQ102 mosfet and BQ 25700 which is known to be good, but the results are still the same, thank you

VSYS_OUT 9.2v
Meter in resistance mode auto range 6M ohm ok

NORMAL BOARD VSYS_OUT 10.2V


PQ101
PIN 2 20V
PIN 7 0.004V
PIN 6 6V
PIN 5678 0V

PQ102
PIN 567 0V
PIN 9 0.004V
PIN 234 9.2V (VSYS_OUT)

PU101 BQ25700ARSNR
1 VBUS 20V...

[rostomzerrougui]

i want to program a W25Q40CL chip but looks like it won't get erased neither programmed
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3265889}[/ATTACH]
Any help ?i want to program a W25Q40CL chip but looks like it won't get erased neither programmed
[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3265889}[/ATTACH]
Any help ?...

[dansity]

Hello,
As a foreword I'm relatively novice with component level audio gear repair. My amplifier stopped producing sound and I currently have no funds to buy a new one so I need any help to repair it. I know "no sound" is one of the most common problem but there were other symptoms so some of you seasoned repairman might able to pinpoint the stuff I have to check. I did download the service manual from manualslib the "no sound checklist" is a bit intimidating.

So i bought it working. First symptom: speaker protection relays on the audio board were clicking...

[aaronkatrini]

Hi all,

I was looking to upgrade my main multimeter (Asita MD591) with something that has more features. I'll use it mostly for board diagnostic and diy repairs. I've been eyeing out many of those multi-function ones from Aliexpress but can't seem to make my mind up. Here are the features that I'm looking after:

- Autorange
- DC volts up to 30V
- Accurate Resistance
- Diode test (Beep mode)
- Frequency up to 200MHz
- Capacitanze up to 5000uF
- as cheap as possible

Other functions are not needed but those which are needed...

[Actionkindaguy]

MSI MEG Godlike x570 motherboard - need schematic and boardview. I have accidentally plugged in the wrong usb plug into a usb3.0 connector on front panel of PC resulting in temporarily shorting out the port. (I know it was really stupid, It was dark in my room and was rushing). I shutdown the computer and now after an immediate restart I get an overcurrent error on boot up saying my PC will shut down in 15 seconds. If I let the computer sit for about 35 minutes, I then can boot the PC without getting error. What I am hoping to find out is what parts were affected by my stupidity. Anyone have any...

[Bonzas]

...

[FZG]

Hello!

I recently got an old VHS player from Panasonic and just for fun I want to try to repair this device. It is an AG-1000B portable VHS player from 1990 and it has a problem with picture quality in playback mode.

Picture in playback mode is very noisy and often loses sync but the still images are nearly perfect.

I want to know, is this something that could be solved by recapping or is the video head likely gone?

Also, what mechanism is this?

Any feedback is appreciated!...

[alltvrepairs]

Hi,

Anyone has a circuit diagram for this Samsung Power supply pls?
QP801CS shorted. Blu Cap is not cracked.


[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image.png","data-attachmentid":3265690}[/ATTACH]Hi,

Anyone has a circuit diagram for this Samsung Power supply pls?
QP801CS shorted. Blu Cap is not cracked.


[ATTACH=JSON]{"data-align":"none","data-size":"full","title":"image...

[Yehuda170]

does any one here have SCH & BV for 820-02655? I see it's available on the web

[aminsab]

bios for laptop model: Aspire one 1-132

snid: 62504891276

probleme : error: turn on but not boot even to the logo


Thank You...

[trepachka]

Hello, this Asus laptop model FA707NU-DS74 has password which prevents computer from booting past it.

S/N: R3NRCX04A476126

I extracted current BIOS from a chip XMC 25RU256CXIQ (1.8V) sitting close to the CPU heatsink.

Please, help me remove the password. Thank you....

[zwerw3]

Hello. Please help. la-g07jp rev1.0 does not turn on. The 3 and 5 volt alarm goes up for 2 seconds and goes out. I opened the 3 and 5 volt power jumpers, removed the pu302, flashed the multimcontroller with different firmware, nothing helped. I noticed that on the u4104 the output is 1.5V, this voltage goes to the combined processor. Should there be such tension there?

[Markus1741]

https://[URL]https://www.badcaps.net... and cause the...

[NootABoot]

I created a supervisor password for my laptop a while back and I forgot it. It can't be reset by resetting CMOS. Can I extract it from a BIOS dump or through another method without a bios/eeprom programmer?

[sam_sam_sam]

This is another battery testing machine that needs to be modified for the cooling fans because these are noisy but not as bad as one of the other battery testing machines that I had modified recently because of it being too noisy

The battery testing machine is going to get two temperatures controlled cooling fans like one I put in the other battery testing machine I just have to remove the temperature sensor and relocate the temperature sensor to one of the heat sinks and put one on the other heat sink so the fan speed can be controlled by temperature

[URL]https://www.ebay.com/itm/186098049856?_trkparms=amclksrc%3DITM%26aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20211130125621%26meid%3D697803b7a1c44f989a96bd22433fa892%26pid%3D101465%26rk%3D1%26rkt%3D4%26sd%3D186098049856%26itm%3D186098049856%26pmt%3D0%26noa%3D1%26pg%3D3650466%26brand%3DUnbranded&_trksid=p3650466.c101465.m3507[/URL]...

[oleinikov_s]

[B]Zbook firefly 14 G9 Шасси (Main Board): 6050a3310001-mb-ax3 i need original bios with ME Cleared, i cant open any bios with FITC 16.1 please help.[/B]

[B]Zbook firefly 14 G9 Шасси (Main Board): 6050a3310001-mb-ax3 i need original bios with ME Cleared, i cant open any bios with FITC 16.1 please help.[/B]

[dimah77]

Please Need to unlock this BIOS
Motherboard x1403za rev 2.2
ASUS Model : X1502Z
S/N : R5N0CV10N87020D...

[trepachka]

Hello,

I have this HP 17-cn1008cy laptop with corrupted BIOS. On boot the message comes up and states that BIOS is corrupted.
Normally, I would download the bios file from HP website but for some reason their software does not run when clicked on it (winflash.exe file). So, I need your help.

S/N: 5CG1425NHD
ProdID: 552Y1UAR

BIOS file is attached. Thank you....

[goodpsusearch]

Recently I was given for free a Sony RCD-W3 with the following symptoms, CD recorder drive reads CDs without any issues (haven't tested recording function yet because I don't intend to burn CDs on that machine) but the reader drive shows disc error after some seconds of it trying to read CD. Tried both CD-Rs and commercial audio CDs with same results.

First thing to do was to clean the lens but that didn't change anything. Googling the issue revealed that this is a common issue on several Sony CD recorder machines and the culprit is SMD electrolytic caps located on the PCB bellow...

[lanlan]

laptop working but when i try to boot in usb, only black coming and stuck

[s_henya]

Hi guys,

Got this EVGA GTX750TI 2GB GPU
MB Bios is beeping when GPU is connected.
When booting with onboard GPU, MB is booting but the GTX isn't showing in windows device manager.
I would like to reprogram the bios EVGA 750Ti 2GB non-6pin 82.07.55.00.50
I searched around but couldn't fins 256kb BIOS like mine.

Anyone can please assist?...

[Mr.heinrich]

Greetings, i just decide to upgrade 8gb on board ram in my dell 5290 2 in 1, is it possible if i just swap the ram chip to 16gb or i should swap the other else like resistor or something. Please help me guys, thank you.

Just for information, my dell 5290 2 in 1 is using SAMSUNG K4E8E324EB-EGCF chip, this is 8gb chip ram.

SERVICE TAG: 160LHR2

Thank you so much.

I'm so sorry if my english isn't clearly.

[crazycavan]

polaroid TQLHD24PR004 no power
hi, my tv no longer starts like dead, no standby led

motherboard : MS36639-ZC01-01
panel : V236BJ1-P01
flash spi: GD25Q64
need usb firmware or to reprogram