Question Can this laptop be repaired ?

[MaximeGeorges]

Hi everyone,

Some month ago, one of my friend probably killed my HP Envy 13 (ad-003nf) by causing an electrical overload to one of its USB port. When it happened, the screen turned off immediatly, and the computer never started again. I bought a new computer since, but as it is a 1300e laptop, I can't just throw it away without trying to repair it.

When I plug the power on, the LED on the start button turns on, but nothing happen, and the Charging Led remains turned off.

I tried to plug an external HDD to an USB C port which can charge an external device even when the computer is not running, and the LED on the HDD do turns on.

I guess the motherboard is dead... Can somebody confirm that ?

Thank you for your response !

Have a great day

 

[vov4ik_il]

For the test of resistance, between pin 4 and the others, here are the results:

1: infinite
2: infinite
3: infinite
5: infinite
6: infinite
7: infinite
8: 1200 ohms

I made the test on the 2000 ohms mode, so infinite just means >2000 ohms. I suspect the 200k Ohms mode doesn't work on my multimeter, values are weird: on pins 3, 7 and 8, value on this mode rise from 10 to 30k Ohms... ( even on the pin 8 where the resistance is 1200 ohms)

The above means the BIOS chip can be flashed without de-soldering. It is safe to try anyway.

Here are the tension I got on these components : https://ibb.co/c8WjFLc

Ok. I believe you skipped checking resistances in those points first. There might be short between one of those and the ground and it is a good idea to check it before applying power (in general).
So far, something does not start on the ones with 0v. Those chokes are usually a part of the voltage regulation circuitry, but the problem might be on the "load" side or in the start-up sequence logic too.
Are there any other chokes like those on the board and underneath the protective film?

1. Are you friends with a soldering iron? SMD/BGP reworking?
2. Do you have access to a thermal imaging camera? (alcohol is a good workaround when something is obviously burning, but it is hard to spot 5C temp difference with it while rising the voltage to raise the heat is going to fry more components, while using thermal imaging makes it a breeze.)
3. Do you have access to an oscilloscope?
4. Lab PSU?

Component-level reverse engineering on multilayer circuitry without schematics is not an easy task. If one of the answers to 1/4 is a "No", your best bet is taking it to a tech who deals with electronic repairs, so he can have a better look into it.

Have a great day

You too

 

[vov4ik_il]

Its so much easier to find shorts when you have power supply and can inject voltage any point you want on the board. Then just use hand to feel which "area" gets hot and freeze spray / isoprophyl alcohol to identify it more.

Everyone has his own technique

About the ch341a programmer he ordered has a 3.3/5v output jumper : https://www.ebay.com/itm/SOIC8-SOP8-Test-Clip-CH341A-Flash-BIOS-USB-Programmer-fur-EEPROM-25CXX-24CXX/114031747365?

I also have old one which has only 5volts, actually it reads 5.5-6v on the multimeter

I have two of those (bought a couple to help that other guy in the motherboard thread... and there is a jumper too, it only controls the Vcc probably). I made the mod (pin28 off the pad and to 3.3v regulator) on one of them to test what it does. It indeed helps.
I tested pins 1-4 (/CS - GND) on the one w/o the mod (bottom ch341a and left DMM) and on the modded one (also added a USB tail to it for convenience).

 

[vov4ik_il]

Hi, I do have a more precise multimeter now. I rechecked impedances of the BIOS chip, between pin 4 and the others. Here are the results on the display:

1 : 5 Mega ohms
2 : 5 Mega ohms
3 : 68 kOhms
5 : 5 Mega ohms
6: 5 Mega ohms
7 : 16 kOhms
8 : 14 kOhms


(Datasheet) : https://www.winbond.com/resource-files/w25q64fv revq 06142016.pdf

You can flash the BIOS IC with a clip, just need to make the mod to that device you bought... But so far this does not seem to be the problem.

For the other chip :

• VIN_SEN (47) : 1.2V
• VDD33 (44) : 3.2V
• VDD18 (26) : 1.8V
• EN (37) : 0v
• PE (36) : 3.2V
• SLP_S0# (35) : 3.2V

After having pressed the buttons, values remain the same.

This IC has to be "enabled" to start the other voltage regulating circuits behind it. The signal might have to come from the ITE IC. You can ring EN leg to all the resistors around KBC and you will probably find one. It does not have to be 0Ω, could be 1kΩ, or even 10kΩ as there is usually a current limiting resistor and pull-up or pull-down resistor on those GPIOs to avoid fluctuation. If you have a laboratory power supply, you can inject 3.3v to this leg and check the other voltages on those chokes that were reading 0, they should come up. But that will not make the board boot.

I did not find any continuity between the "not groud pin" of the power button and any pins of the KBC. I will recheck later to be sure...

Same as above, there should be a resistor. Ring on the outside of the resistors. The KBC seems to have 128 pins, some will probably be between the layers or on the bottom of the board. I looked up other ITE 128 pin KBCs (1, 2) and the power button may possibly be pin 18 or 21, but it does not necessarily have to be the case here. You can try waking it up by checking what does it have on sleep (0 or 3.3v and applying the opposite via 1kΩ resistor.

I do not see a better way to continue troubleshooting beyond this point without schematics for it (KBC Datasheet). These controllers are usually either pre-programmed or self-programmable on first boot, but once programmed have to be cleared with jtag to program again. If it is faulty and needs to be changed - getting a new one might not be enough to get things working again. You will also need some tools to replace this BGA.

 

[hang-the-9]

No way to confirm where the issue is without swapping parts, but it does seem like the motherboard is bad. Did you try anything already aside from just trying to turn it on?

 

[lga1156_ftw]

Look all the usb 2.0 or 3.0 ports on the laptop , does the pins/array look fine or something like this : https://linustechtips.com/main/topic/886615-broken-usb-port/

 

[MaximeGeorges]

Hi all and thank you for your answers,

I opened it and removed the motherboard. As everything on this laptop is directly on the motherboard, the problem must be on it.
I looked at the USB port, they look perfectly fine.. The electrical overcharged was made with a 12V tension on the USB, which is not much, so there are no visible damage on the motherboard neither.

Here is a photo of the motherboard : https://ibb.co/D7PnX8Q

I might just be a soldering, but again I don't see any damage on the motherboard...

I saw used motherboard on ebay from the same model, at a correct price. As everything on this laptop is directly on the motherboard, apart from battery, screen and SSD, changing the motherboard is radical but should save my laptop right ?

If you think on anything I would be glad to hear ! The fact that when I plug the alimentation of the laptop in, the led of the Start button turns off makes me think that the problem might not be so big...

Thank you !

Ps: sorry for my english, it is not my mother tongue...

 

[lga1156_ftw]

Can you flip the board and take another high quality picture?
Motherboard model is written somewhere on the board itsef, might be under tape.

You can test few things, plugin external monitor on the hdmi port.

Plugin the DC- in cable (where power cable plugins)

Keep the heatsink connected

Remove cmos battery / battery connector (round coin battery might be on the other side of the board)

Put the motherboard in non conductive table, look that nothing is shorted

Remember when you start the laptop you have short window to test if it boots / you get picture since fan is not connected and cpu heats very rapidly, around 20sec and you need to disconnect the power cable.

If there was no cmos battery, you need to get the power button cable from the front cover and plug it in the motherboard, if there was cmos battery it should boot straight away when you plugin power cable, no power button cable needed.

Test if you get picture on the external monitor or power leds, / etc. This means cmos clear fixed the issue or you killed another component on the system like LCD, keyboard etc if you get picture on the screen,

Plug off powr cable after test, plugin the power cable connector (if you booted without cmos battery and didnt need it before this) Plugin the battery to the motherboard connector and try to boot WITHOUT power cable. plug off battery fast if you get picture.

 

[MaximeGeorges]

Thank you for your answer,

First, I do not have any removable cmos battery on it, as you can see on the other side of the board, which is quite empty : https://ibb.co/GkLCxFY

However, I do have these little connectors, but I do not know how to operate with them. (Connecting them with a wire, without DC IN ?) : https://ibb.co/NVtsSDw

I tried what you said, by plugging DC IN and an external monitor, and then pushing the start button, but nothing happened, and there were not heat around the CPU, even after 10 seconds.
The LED on the start button which do turn on are the only living sign of the motherboard.*

I could probable get a multimeter, is there any component or soldering I could theck ?

Otherwise I will probably try to get a working motherboard on ebay...

Thanks again

 

[lga1156_ftw]

Try shorting the cmos pins for 10sec

 

[lga1156_ftw]

Something might of caused bios corruption but theres no point if you dont get 3 volts To the bios chip. Multimeter with fine tips Is nice. But can you remove tape near the usb ports and Look if there Is anything odd there?
You can also get usb ch341a programmer those are like 3 euros shipped

 

[MaximeGeorges]

Hi,

I did what you told, shorting the pins for 10 seconds, with DC IN plugged. But nothing changed.

Do you have an idea of where I could find the bios chip ?

I looked under the tapes, and found out that there are 2 soldering that seems to be damaged. Actually if we compare them to the other soldering, it seems like there is no soldering tin on them anymore : https://ibb.co/CHgbJBn

About the programmer, what is it used for ?

Thanks

 

[MaximeGeorges]

Hi,

Small update, I found the bios chip which was this one : http://www.bios-chip24.com/Winbond-25Q64FVSIQ-64MBit-SPI-Flash-SOIC-8/fr

And after a multimeter test, it is correctly powered with 3V.

 

[lga1156_ftw]

Voltage on bios chip (pin1) means that KBC is fine, check pin 8 too, rest is hard cause you would nee d oscilloscope to measure them (signals). Also was that the usb port which caused the issue in the first place? Can you take pic of other side of board on that USB port.

Also get yourself one of these CH341a programmers you can check with this if bios is corrupt:
https://www.ebay.com/itm/SOIC8-SOP8-Test-Clip-CH341A-Flash-BIOS-USB-Programmer-fur-EEPROM-25CXX-24CXX/114031747365?

Soic clip is useful if you dont want to desolder the chip from the board, but is not necressary.

 

[MaximeGeorges]

Both pin1 and pin8 are alimented with continuous 3V. It happened 1 year ago, but there are only 2 USB A port on this laptop so it is probably this one.
But as far as I can see, these soldering are there to maintain the port on the motherboard, and even if the soldering is damaged, it is still connected to GND ( I tested it)

For the other side : https://ibb.co/rHTZV2q

When the surcharge happened, the computer turned off immediatly, do you think that it would have happened if the problem was only a bios corruption ?

If yes I am gonna buy the programmer and see, even if I do not know I to use it, i'll find out.

Thanks

Ps : the programmer you sent me is described as compatible for eeprom 25CXX. On mine it is written 25Q64. Will it work anyway ?

 

[lga1156_ftw]

Things like this might corrupt bios and ec. Can you confirm motherboard model number, written on 2nd picture of the motherboard its just so small text , is it 6050A2919201 - mb -A01?

Yes i have flashed w25qxx chips with ch341a but there is sometimes problems with using the soic clip, when you flash the chip using a clip you are literally powering the whole 3.3v circuit on the motherboard. These programmers are not always capable of doing it and you need to desolder the chip and solder it into addon pcb (included in that)

 

[MaximeGeorges]

Hi,

Yes, this is the correct number.

I do not have what is necessary to solder it after that at the moment ... So I would not even be able to test if it works afterwards

 

[lga1156_ftw]

Are you getting voltage on the power button pins?`If yes try this below (first remove all connectors from the motherboard just try boot it barebone only power cable connected:

If power button board is not working (this is crapshoot) you can try to plugin power cable and short pin3 and ground on power button connector (on the motherboard). This should boot up the pc without power button also.

Can you remove all tapes from the motherboard and look if theres anything odd looking under, including heatsinks?

And for bios chip, IF soic clip method dont work:

You can do it with soldering Iron too. Like this :

View: https://www.youtube.com/watch?v=LHMmG3NuM9U

There is not much room for error when looking at the spot where your bios chip is.

Here is a very good guide on how to do it : https://forums.tomshardware.com/thr...asher-1-8v-adapter-and-a-soic-8-clip.3593910/

 

[MaximeGeorges]

I do have 3v on the 2 pins located at the top of the power button, and the others, located at the bottom, are connected to the ground. When I press the button, the 2 pins at the top go from 3V to 0V, and become 3V again when I release it. So it seems to be working right ?

Here is what is behing the heatsink tape. It looks ok to me... : https://ibb.co/sbmr61T

I boought the programmer, I am now waiting for it, might be quite long ...

Thank you again for the help, much appreciated !

Have a nice day

 

[lga1156_ftw]

Looks fine, what programmer did you buy? Power button seems to work, there might be short somewhere.

Trying to reprogram bios would not be my first step if i had the motherbord myself, but since i dont have schematics for it its worth a try. And this programmer is very useful for its price, you can reflash any desktop or laptop with it, fixing laptops with bricked bios and also you can try modded bios and do it yourself too since there is always backup you can reflash if something goes wrong.

 

[MaximeGeorges]

I bought the programer you told me

I watched some videos about how to diagnostic a dead motherboard online with a multimeter, but It did not help..

At first I was considering the fact of buying a new motherboard (~250e), so if reprograming the BIOS does not work I will do that...

If you can suggest me something else, for instance to locate the short or anything, I am always interested.

Have a nice day.

 

[lga1156_ftw]

So we know 3.3v line is present, what about 5v line which covers USB ports ?

Put the cmos battery back in and plugin power cable, after few minutes test with your finger if you find some area getting hot on the motherboard. Then use isoprophyl alcohol 90%+ just drop it on the hot spot and see what component evaporates quickliest, its not conductive.

I sometimes use this method if i dont have isoprophyl alcohol :

View: https://www.youtube.com/watch?v=AOALg_rDIZk


Thing is most likely no area gets hot since short is isolated within a power line (example fuse blown) and you would need to use external power supply to inject voltage other side of the dead component to see what is causing the short.

If nothing gets hot with power adapter , unplug the power cable. You can find the short pretty easily by measuring different lines with continuity (obviously do this WITHOUT any power plugged in, never measure continuity with any voltage)

 

[MaximeGeorges]

I do not have Cmos battery, or at least none that I can remove. But after several minutes, no parts are getting hot...

I am gonna try to find the short by testing continuity !

Edit : I think I found something. One usb port is powered by 5v, but the other one on the other side of the mb (The one on which I found some damaged soldering earlier) gets no alimentation. So it must be this port that has been overloaded.

 

[lga1156_ftw]

Okay remove power cable and check it for short with continuity.

Was this the port which caused it to die in the first place?

Do you mean after pressing power button, you need to remember there is usually some ports which power peripherals when the machine is shut down, and some ports get voltage only after power on. "Always on USB"

 

[MaximeGeorges]

Yes i am quite sure it was this one

I mean when the power cable is plugged in, only 1 USB port is alimented by 5v .

The usb C do power peripherals when the machine is shut down, but not the USB 2.0, not on this computer at least. And the soldering that is used to power the usb port with 5V seems to be damaged, when I compared it to the other USB 2.0 port. By damaged I mean there is a lack of soldering compared to the other.

Thanks