Develop Bugs

[Q] Help! - DZ Repair Mission, Advice Needed.

My First Post! How's it going everybody! (Newb Alert)
I just purchased a Bell HTC Desire Z from a classified ad off of an older man who found that the phone wasn't fully functioning. The poor guy probably paid around $400CDN for the phone, but I ended up eventually buying it from him for $250.
Here is what is wrong with the phone:
1. Power Button-does not work, neither on or off...basically fully unfunctional and only way to turn phone off is battery pull...fun stuff! (planning on using the Teardown/Repair guide by verkion - recommended?)
2. The In-Call speaker (where you put your ear while talking on the phone) seems to have very limited sound, perhaps something has been destroyed on the inside, how all other sound mechanisms work, such as the external speaker and internal speaker w/ headphones. (planning on using the Teardown/Repair guide by verkion - recommended?)
3. The Digitizer, well parts of it (along the left edge of the phone when upright) are unresponsive, so called blind spots which when touched are unresponsive on the digital keyboard along with the home button (house shaped icon) - especially frustrating when browsing web pages because I have to click back like 10 times to get home... (planning on using the Teardown/Repair guide by verkion - recommended?)
4. It is a Bell branded phone, Locations does not work! however I have done the research on the forums and I think I can figure out the whole Rooting thing out, but advice is appreciated! (planning on using gtrab's FAQ for Dummies for the rooting, s-off, and de-branding)
Now...I am not really technologically inclined to the level most of you probably are, but I am good with my hands and really interested/curious about this whole mission I need to complete, so I can fix this phone myself instead of paying $100 for cell phone repair...plus its a nice challenge right?
Do you guys recommend that I take care, or at least attempt to fix the power button issue before I root the phone to a previous, unbranded firmware which will allow me to use Locations? This only makes sense right, because I am going to need the power button for that process?
I know this is a lot to ask, but I just need some pushes and shoves to get me on the right track to try and get this to work, so if it is technologically impossible or excessive...please let me know how I can fix 4 of these problems methodically in a safe and professional way!
Once again, I appreciate it.
Thanks in Advance
EDIT: My prediction is that the individual who originally owned this phone dropped it and as a result the digitizer, power button, and speaker were all affected...but of course I am no expert.

To me it sounds like the flex cable has been damaged. It would definitely cause all these things at once.
I'm pretty sure you need to fix the power button before rooting because you need the power button to actually root it.

Hmmm,
Never thought of that but it sure seems like a better diagnosis. The flex cable originates in the bottom half of the phone in the same compartment that the z hinge is found right?
It is also the flexible strip that runs through the middle of the phone when the hinge is half-way positioned, connecting the lcd/digitizer to the main motherboard of the phone?
I geuss replacing the flex cable would still involve the Teardown/Repair, however I dont think I will need to replace a power button, speaker, or digitizer IF!...that is the case.
Any other ideas on this?

TheToiletSpaula said:
Hmmm,
The flex cable originates in the bottom half of the phone in the same compartment that the z hinge is found right?
...
It is also the flexible strip that runs through the middle of the phone when the hinge is half-way positioned, connecting the lcd/digitizer to the main motherboard of the phone?
I geuss replacing the flex cable would still involve the Teardown/Repair, however I dont think I will need to replace a power button, speaker, or digitizer IF!...that is the case.
Any other ideas on this?
Click to expand...
Click to collapse
Yes thats the flex cable, it is built into the pcb behind the lcd, so the whole pcb has to be replaced AFAIK. Yes it requires a full tear down to do it, fairly basic to do, my phone is in pieces atm because the lcd needs replacing.
If the flex cable is the problem then none of those parts need replacing, it would be very unlikely in my opinion for all those parts to fail from a drop without it being flex cable related, possible though.
Link to the teardown, some steps in the middle are unneccesary for what you need. http://tjworld.net/blog/htc-desire-z-tear-down

elliott2705 said:
Yes thats the flex cable, it is built into the pcb behind the lcd, so the whole pcb has to be replaced AFAIK. Yes it requires a full tear down to do it, fairly basic to do, my phone is in pieces atm because the lcd needs replacing.
Click to expand...
Click to collapse
Hey, do you know where I can get a replacement pcb if I decide to take that route man? Seems hard to find that as a single part for sale...
I assume people replace their whole phone if they have a problem like mine :/

You wasted your freaking money on that phone!
250 is a huge waste!
You might as well add a line to your friends for the contract price.

melodicjunkie said:
You wasted your freaking money on that phone!
250 is a huge waste!
You might as well add a line to your friends for the contract price.
Click to expand...
Click to collapse
it's not THAT bad...considering a brand new one unlocked DZ goes for 450+ and i knew I could fix parts of the phone so for -200 cheaper...i don't know bro!
I just need to know if a replacement pcb is possible to get, or maybe just the flex cable is damaged in which I wouldn't need to replace something so crucial.
Who knows what to do?
EDIT: 450 where I live...Ontario, CA.

...i dunno...could even be water damage that did the deed to that phone....in which case you could be replacing a pcb...or not....I've seen water-loged phones come back to life before....sad thing is it might cost you a few to fix it properly...
Totally agree 250 was to steep...that guy probably paid 79 on contract for it....
Sent from my HTC Vision using XDA App

tvnaderwal said:
...i dunno...could even be water damage that did the deed to that phone....in which case you could be replacing a pcb...or not....I've seen water-loged phones come back to life before....sad thing is it might cost you a few to fix it properly...
Totally agree 250 was to steep...that guy probably paid 79 on contract for it....
Sent from my HTC Vision using XDA App
Click to expand...
Click to collapse
Wow about the whole coming back to life thing you just said...thats exactly what my digitizer just did, so the left side of my lcd is now working including the home button!
Im guessing the touch panel ribbon was loose but it somehow shifted to functionality.
Great...now for the in ear speaker and power button, and 250 wont seem too bad!
Edit: anyone know how I can look for past signs for water damage like a colored change in a sticker or something?

TheToiletSpaula said:
Wow about the whole coming back to life thing you just said...thats exactly what my digitizer just did, so the left side of my lcd is now working including the home button!
Im guessing the touch panel ribbon was loose but it somehow shifted to functionality.
Great...now for the in ear speaker and power button, and 250 wont seem too bad!
Edit: anyone know how I can look for past signs for water damage like a colored change in a sticker or something?
Click to expand...
Click to collapse
There are 2 water damaged indicator stickers, 1 under battery and, 1 under the back housing, you can see it through the opening where the top tab of the battery door latches.
Edit: Forgot.... 1 on the battery too.

What color would the stickers be? They are both white, does that mean anything?

If they are pink they got wet.
Sent from my HTC Vision using XDA Premium App

^^ What they said.... Pink or Red

250 is quite a bit for a device with issues, but good news is it isn't water damage by the sounds of it.
I'm an aviation electronic tech, and your symptoms definetly sound like a loose interface ribbon. If I were u id haul it apart and reseat the flex cable you guys are talking about. I would put a 85% chance that's the issue.
good luck, and welcome fellow canuck to xda and dz family
Sent from my HTC Vision using XDA Premium App

Sounds good guys.
However...even if it is probably the flex cable that is causing the remainder of my problems:
1. the in call speaker being super quiet
2. power button not working
Is there any other chance that the speaker and power button areas have loose connections? what should i look for when i open the phone aside from ribbon/flex cable connections?
I need to get the power button fixed because then i can move onto rom modifications and stuff to finally get locations!

[Q] Water Damaged Galaxy Nexus

Hi all,
My brother recently dropped my prized 2 day old Galaxy Nexus in the toilet and after 4 days in a bowl of rice it starts up fine (although randomly reboots sometimes). However, the touchscreen is being very temperamental. Most of the screen works fine, however the bottom area only works about 10% of the time if I press very hard. By the way, its my first time posting on XDA so if theres anything I've done that is stupid/nooby or whatever please tell me. Its impossible to improve if you don't know what you're doing wrong
I'm running Cyanogenmod 10.1.3 and although I could upgrade, I don't want to do anything unninteruptable in case my phone reboots during the process. My Galaxy Nexus is a GSM version on T-Mobile UK and its one of those limited edition Google ones that they give to employees (google it (I can't link because its my first post) if you don't know what I'm talking about... Also, can you try to refrain from saying 'get it fixed' or 'get a new one' as those things cost money, and money is one of the things a 12 year old boy doesn't have (the phone is my dads old one - he got a nexus 5 recently and passed this down the line to me...)
I'm pretty good with computers and phones (hackintoshed every computer my family own, all our androids run cyanogenmod, built my own webserver) and I can follow instructions relatively well so don't feel you have to limit the difficulty of your answers because of my age
(by the way, we should ask someone here to add a toilet post icon, considering the amount of threads there are about phones dropped in the loo )
Just realized this is in the wrong forum, can someone help me out and tell me how to move it?

freddy362 said:
Hi all,
My brother recently dropped my prized 2 day old Galaxy Nexus in the toilet and after 4 days in a bowl of rice it starts up fine (although randomly reboots sometimes). However, the touchscreen is being very temperamental. Most of the screen works fine, however the bottom area only works about 10% of the time if I press very hard. By the way, its my first time posting on XDA so if theres anything I've done that is stupid/nooby or whatever please tell me. Its impossible to improve if you don't know what you're doing wrong
I'm running Cyanogenmod 10.1.3 and although I could upgrade, I don't want to do anything unninteruptable in case my phone reboots during the process. My Galaxy Nexus is a GSM version on T-Mobile UK and its one of those limited edition Google ones that they give to employees (google it (I can't link because its my first post) if you don't know what I'm talking about... Also, can you try to refrain from saying 'get it fixed' or 'get a new one' as those things cost money, and money is one of the things a 12 year old boy doesn't have (the phone is my dads old one - he got a nexus 5 recently and passed this down the line to me...)
I'm pretty good with computers and phones (hackintoshed every computer my family own, all our androids run cyanogenmod, built my own webserver) and I can follow instructions relatively well so don't feel you have to limit the difficulty of your answers because of my age
(by the way, we should ask someone here to add a toilet post icon, considering the amount of threads there are about phones dropped in the loo )
Just realized this is in the wrong forum, can someone help me out and tell me how to move it?
Click to expand...
Click to collapse
To try to solve the problem you have to disassemble the phone, remove the water that still inside and clean the oxide on the surface of the connectors, because the Gnex is formed by separate PCBs in order to make easier the repair, but if some water goes inside the connector, a shell of oxide will be formed on the pins and the connector can't work well as it should...
The only thing you need is a very small cross screwdriver, a can of WD-40 (That is originally made to move away the water, but it is also useful to clean the contacts from the oxide and of course it can't conduct electricity) or any other similar product with the same characteristics (you can find it in pretty all the hardware store), and this guide Samsung Galaxy Nexus Teardown.
When you get all the spare parts of the phone disassembled, spray the WD-40 on it, in order to remove all the water and humidity (Just put attention to not spray inside the both earphones and the cameras, or you will have to manually remove the oil from inside the earphones with compressed air and clean the cameras with some cotton swabs). Then with a cotton swab and WD-40 clean all the contacts of the connectors.
Now you have just to reassemble the phone, following in reverse the guide of iFixit.
Just check before if the USB port fully work (fast charge from AC adapter, slow charge and data transfer from PC), because when happens to me was the only part that i have to replace, bought for 3$ from eBay...
Don't worry is easier to do than to describe how to do...

Dry Patrick said:
Very useful advice
Click to expand...
Click to collapse
Ok thanks for the help

Oh, if you have rubbing alcohol around, try rinsing the PCB with it, it helps too.
Next time water gets in your phone, immediately disassemble it and rinse it with rubbing alcohol to remove the water, then put it on a dry cabinet(if you have one) or seal the PCB in a box with desiccants.
Beamed from my Grouper

[Q] Transplant Surgery - T999 mainboard into SCH-I535/SPH-L710 body

I have been looking around, but no place specifically answers this exact question.
Long story short I have a t-mobile Mainboard that I want to save from a phone with a broken screen that I have. From what I understand the other components work as well (camera, speaker and whatever else). I understand that I can purchase an LCD/digitizer with assembly and carefully place the components into there to make sure the phone works but it would cost me around $120 for the parts + whatever time it takes me to replace the components. My second option which I am asking to see if it is indeed possible, would be to take the mainboard from the T-999 and replace it with a SCH-I535/SPH-L710 that I would purchase (most likely with bad ESN - costing me the same amount) but it would mean that I would not have to deal with screen replacement and I have a higher likelihood of having a good quality screen. (I have never been happy with the quality of screen replacements from ebay). It makes no difference if it doesn't work, but someone with the experience of working with different models should be able to answer this question.

Why not buy T999 with bad ESN ?

Perseus71 said:
Why not buy T999 with bad ESN ?
Click to expand...
Click to collapse
I am trying but T999 with bad IMEI's are not only more expensive but a lot of them also have broken screens so im back where I started. I am just stating these two because I can find them cheaply and easy to find as well.

In that case, you could try taking the Display & Digitizer from those phones and put it in your phone. Don't try to transplant your motherboard into that phone unless you have a good reason to do so.

It functions but you have to use a case and...
I did this a about a week ago. Here's how it went.
I bought a SPH-L710 without realizing it did not have a sim card slot. The screen had one slight crack and everything else worked.
After receiving it, I bought a T999 with a cracked screen/ non-working digitizer and everything else worked (the seller heard sounds when it powered on.)
I disassembled both and put the T999 mainboard on the L710 screen digitizer. Most of the screws line up. The two screws that don't line up are:
1. at the bottom near the TOP of the USB port. The hole in the board and the hole in the digitizer are on opposite sides of the USB port. This cannot be remedied, where the screw goes through the board, there's no hole on the digitizer, and you can't put a hole through the mainboard to meet up with the one on the digitizer. You could try but I think there's a circuit on the board there, or not enough room.
The two holes on the SIDES of the USB port will line up only when you squeeze thee mainboard and digitizer together while installing the screws.
2. on the side near the power button, there is a screw that goes there, but on the T999 mainboard near where the screw goes, there's something that looks like a button cell battery about 3mm wide and 1.5-2mm tall. It stuck in a hole made for it in the T999 digitizer, but the L710 digitizer does not have a recess in it to fit this button cell so the T999 mainboard sticks up slightly, enough that if you put the screw in the hole in the side, then the power switch on the mainboard will not stick down far enough, and when you push the power button on the outside of the case, it won't engage the power switch on the mainboard. To remedy this, leave out the screw on the side of the mainboard.
Because the mainboard is slightly bent due to the button cell battery, you need to have a case that compresses the phone together so the power button will engage the power switch properly. I used a "waterproof" chinese knockoff case I got on e$ay for $13. It's not waterproof, but the phone didn't get ruined even thought I tested the waterproof-ness of the case before I put the phone in and it passed, so maybe a genuine otterbox case would have been better. But the case does OK to compress everything enough that the power button and power switch work all the time. With the case on, you can't tell the phone is missing screws internally.
Verdict: everything works properly except the camera doesn't focus properly, it only works in Macro focus, I don't know if I should take the camera module from the L710 and try it or if it won't move because of the stress of the mainboard being slightly bent all time due to the button cell battery. It did focus properly for the few few days I had it.
One other issue: I can't get Windows 7 to recognize it, so I can't use Odin to root it, I've tried all the drivers, I've tried all the modes. I have no idea if this is a Windows issue or if it is somehow caused by the Frankenstein's Monster-ness of the hardware.
So yes, it can be done, with a "rugged" style case and with a few issues. I have no experience with the I535 at all.
I hope this helps,
rollinns

I could not have asked for a better reply. Thanks so much!!!!

Glad I could help
I was looking for this info about 3 weeks ago and didn't really look that hard since i was pretty sure everyone would give me the same replies you got before I replied. But for my entire life I've been asking questions no one else has asked, so I'm used to just having to do stuff to get answers. In this case, it helped you too.
If I had to do it over again, I think I'd try the whole process w/o the L710 parts. Maybe the I535 will work, and I still could drill a recess into the L710 digitizer if I had a mill, but I don't have access to mine now and won't for a while, and I'm not sure I trust the drill press to not crack the digitizer.
Also - NFC is less reliable than it was with my S2, meaning it doesn't work all the time - it's harder to beam contact info to another phone, but QI wireless charging works flawlessly.
My hope is to put some NFC tags in the truck along with a wireless charger so I can listen to internet radio as I drive, i.e. - a tag to turn off wifi, turn on bluetooth, turn on the app that streams music to my JVC car stereo and turn on the "TuneIn" app. and then I can still charge my phone without worrying about wires.

[FIX] GPS issues, antenna cases only E98X, requires disassembly.

I thought this was worth sharing, this is my second thread ever on XDA and hope it helps somebody.
Quick story about my case:
I tried software fixes, ROMs, and made a lot of reading, when I finally figured it could be an antenna issue, I decided to give myself a try on my cellphone repair skills, turns out I turned a “nearly dead” GPS taking 10 minutes to lock into a “better than average” GPS taking 20 seconds to lock. Time taken for the task, 15 minutes, time suffering from bad GPS signal, 1 year, go figure.
Let’s see if you are a candidate to try this solution:
- You must be sure this isn’t a software related issue (i.e. my GPS works with X rom but it doesn’t with Y rom, that would certainly be a software issue).
- You CAN get a GPS lock but the signal is weak (i.e. constantly dropping signal in an area where you are sure another phone works fine) or GPS locks takes up to 5 minutes (and you already tried a software fix to speed up GPS lock).
- You’re phone is relatively old (i.e. it was bought when it came out, although I’m sure the quantity is low, I assume there are still E98X phones which are brand new and I would not recommend disassembling a brand new phone).
- You have experience opening cellphones (i.e. experience using small phillips screwdriver, gently popping frames/housing/covers, putting back in position plastic buttons before re-assebly).
Before we start, quick explanation on what may be happening to your phone if you are a candidate:
- Presumably, the GPS antenna (and Bluetooth, 3G/4G as well) is making poor contact with the springs on your phone.
- This phone uses contact springs for pretty much everything (see attached picture for springs locations of antennas), so these springs and/or the antenna contacts eventually bent away from each other and lower your GPS, Bluetooth, 3G/4G signals.
Here is what you need to do:
- Remove the back cover, and remove the back frame (See the following video from minute 0:00 to 1:50 for disassembly of backframe https://www.youtube.com/watch?v=S9OJRtf39QA).
- Inspect every spring and antenna contacts (see attached pictures for antenna springs and pad locations), make sure they are not rusted or damaged, else you need a replacement part for it (for antenna pads, you may want to clean those with isopropyl alcohol if you have some).
- Using a soft, thin, *plastic* tool (thinner than a credit card, but sturdier than paper), lift every spring you see up to 10 degrees (see attached picture for reference) and wiggle it up and down to force it to stay tilted up about 10 degrees (don’t force it up more than 15 degrees when wiggling or you risk to break the spring, there are quite a few of springs, I remember at least 5 pairs, so make sure you get them all done).
- Revert all disassembly made (See the following video from minute 6:32 to 7:51 for reassembly https://www.youtube.com/watch?v=9QxLa5rXX7Y), and VOILA!! your GPS signal came to life again (and hopefully your Bluetooth and 3G/4G are enjoying the new perks too!)
-Additionally, better 3G/4G signal does save battery, your cellphone amplifiers require less work and produces less heating too.
Disclaimer: I’m not responsible for damage to your phone, this guide is intended for an grown up audience who takes responsibilities of their own actions.

Reserved

Jose-MXL said:
Reserved
Click to expand...
Click to collapse
I was looking for something like this. Thanks very much..........

Let me know if you need anything else (i.e. more detailed instructions) and report back your results, unfortunately for the audience, I didn't take pictures of the process since I wasn't sure it was going to work (and then just took the picture of the NFC springs), so if you can take some pictures of how the contacts looks in the inside, that would awesome, I can update the main post with these, there is quite a few springs inside so you want to make sure you get them all in shape.
I forgot to say in the main post, better 3G/4G signals give a lot less of work to the amplifiers, which means less phone heating and less battery consumption, this is a nice service to do to a 2 year old phone like mine.

Enclosed is a picture from a replacement mid frame cover. Could you please use something like ms paint to circle which pins you bent upward? Looking at my Optimus G Pro 980 Mid frame cover and motherboard/logicboard I do not see these........
Jose-MXL said:
Let me know if you need anything else (i.e. more detailed instructions) and report back your results, unfortunately for the audience, I didn't take pictures of the process since I wasn't sure it was going to work (and then just took the picture of the NFC springs), so if you can take some pictures of how the contacts looks in the inside, that would awesome, I can update the main post with these, there is quite a few springs inside so you want to make sure you get them all in shape.
I forgot to say in the main post, better 3G/4G signals give a lot less of work to the amplifiers, which means less phone heating and less battery consumption, this is a nice service to do to a 2 year old phone like mine.
Click to expand...
Click to collapse

jmacguire said:
Enclosed is a picture from a replacement mid frame cover. Could you please use something like ms paint to circle which pins you bent upward? Looking at my Optimus G Pro 980 Mid frame cover and motherboard/logicboard I do not see these........
Click to expand...
Click to collapse
UPDATE:
See main post, I got a picture from somewhere else for the spring locations.
Actually my friend, that picture only shows the pads for the antennas, try to match it with your phone and see where they contact, these are going to be the springs, they don't look like spiral springs, these are other type of springs which I don't recall the name but they are more like a V shape, and one of the sides is attached to the board and the other one "springs" up and down, let me know if you got it or I will open my phone again, just for you! (no kidding)
Also, if I were you I would try to do the same for all pairs of springs I see on the motherboard, there is a pair for the speakerphone and one more down the board for something else.

GPS finally fixing
Thank you so much for this post. Before this solution, I tried different roms, gps fixing apps, disabling carrierIQ, editing the gps.conf file to add "better" servers, etc. This is the only solution that really worked. Now I am getting a GPS fix in 10 to 15 seconds where before it was up to a minute or more. I have an LG E980 (ATT Version).
As directed, I turned off the phone, removed the rear case back, removed the battery+sd card+sim card, removed the screws in the back panel of the phone and then separated the back panel from the front panel to expose the circuit boards and spring contacts. Then, I cleaned all the spring contacts and their mating flat contacts on the back panel with alcohol. Then I bent all of the spring contacts up slightly, re-seated the back panel making sure the side buttons were in the correct place (I do not believe the quickmemo and power buttons are interchangeable even though they are the same size fyi), and then secured the screws back in place.
Thank you!

Way to go buddy, I'm glad I could help you and that you were able to follow those horrendous instructions, I can't be sure on your case since yours wasn't as bad as mine, but on my case it also improved 4G reception overall, these antennas are used for pretty much everything so it would only be logical to get better signal on all the services, this is a "must" service on old E98X phones, perhaps nearly half of the GPS and bluetooth issues on the forum are due to this plus a weak or faulty software filtering not helping.

any info how to increase the wifi antenna? could this be the white cable?
Sent from my LG-E980 using XDA Free mobile app

I've quit using my OG Pro because the GPS is so poor. Hard to get a fix and drops constantly. Glad I stumbled on this, and will give it a try.
Can you point out which springs are specific to the GPS antenna? I suppose I can try to work with all the springs, but with my luck, I 'll break something that was working fine.

fungo45 said:
I've quit using my OG Pro because the GPS is so poor. Hard to get a fix and drops constantly. Glad I stumbled on this, and will give it a try.
Can you point out which springs are specific to the GPS antenna? I suppose I can try to work with all the springs, but with my luck, I 'll break something that was working fine.
Click to expand...
Click to collapse
I don't know which ones they are. I did all of them. They are a lever type spring contact so it is hard to break them. Just do so lightly.

Wow fairly simple fix with great results, thanks!

Jose-MXL said:
Before we start, quick explanation on what may be happening to your phone if you are a candidate:
Click to expand...
Click to collapse
Just tightening all the screws fixed all my GPS issues. No disassembly required! Add this into OP.

Thanks
Just did this, really improved the speed and reliability of everything- gps, wifi, etc. Thanks.
A quick tip for those doing this the first time. be careful of the buttons. I've taken apart my optimus g pro a few times now, and those dern things like to fly out of you're not careful when taking it apart. Also, when putting back together, use a small piece of scotch tape on the exterior of the frame to hold the buttons in place when you put the frame back in place. make sure the tabs of the tape stay on the outside, and pul them gently as you snap the screen back on. It's easier to have the frame on the table on put the screen down onto the frame when done this way, and save those dern buttons from coming out of their slots.

I have two OG Pro (E980) developed same broken GPS issue.
Now, I think the problem is the two soft contact pads, when I bent little bit, the GPS 's issue got fixed.
Also, the method not to improve any 4g/Wi-Fi/Bluetooth.
LG made such low quality contact PINs

Two years have passed and this thread is still helping people with their now "ancient" G Pros. My problem was that the coax cable had popped loose. Still I went ahead and re-tensioned all the contact springs. GPS is now functioning like new. Thanks to all who contributed.

Strange Lg G3 (D855) issue

Hi all,
Firstly apologies for the long post but I feel the more information I can supply the better diagnosis might be made.
I was recently given an LG G3 D855 16GB/2GB phone which has a very intermittent issue of rebooting and throwing a blue screen, notably it seems after I run any app updates. I have so far done the following to try to fix it:
1: I managed to get it working long enough to get all my friend's pics and movies etc off, then performed a factory reset using vol down and power button. Phone booted up fine, I could proceed through the setup options. Took it to work and using LG PC suite upgraded to Marshmallow. No issues.
2: Updated two apps from Playstore, rebooted and got a blue screen and reboot, but eventually it came right again and I was able to use it for a while.
3: Ran another update from Playstore and got a blue screen before the update was even installed. Left it alone for about an hour with the battery out then booted up and did a factory reset again with back buttons. All good, ran through setup no issues.
4: After using it for a few days I decide to try to update again, and again blue screen and reboot. This time did not come right even after leaving it.
5: Downloaded KitKat TOT and DLL files for my specific area or zone, South Africa, and managed to get the phone into download mode then used LG Flash Tool v 1.8.1.1023 to install ROM from TOT file. All went well. No issues at all.
6: Used for about a week then upgrade to Lollipop via LG PC Suite. Again, no issues whatsoever.
7: Next day decide to do updates, updates went fine until I rebooted then blue screen, followed by green screen with the demigod kernel crash message and reboot. However, I just left it to do its reboots and after about 5 or 6 times it booted up and stayed running.
8: This past Monday I upgraded to Marshmallow using LG PC suite, no issues whatsoever.
9: Yesterday I ran one update and rebooted, blue screen and rebooting. Took battery out and left it for about an hour again, put battery back in and did factory reset using back buttons.
10: As of right now phone is functioning perfectly again.
I must mention the following:
1: I can install any app that gets wiped when doing a factory rest, like WhatsApp, Nine Email, GBoard etc with no issue whatsoever.
2: The battery is fine as far as I can tell, it lasts about 3/4 of the day under normal to heavy usage and is not swollen at all.
3: The Phone NEVER gets hot at the back, even when rebooting constantly or throwing a blue screen.
4: As far as I know it has not been dropped.
5: It is protected by the LG QuickCircle case with QI charging back.
My question after all this is, could this be a hardware (Motherboard) issue or is it software somehow? I really like this phone when its working correctly so would love to be able to use it with no worries.
Any guidance at all from the wonderful smart people here at XDA will be highly appreciated!
Thank you for your time and patience!

Blue screen is, I think related to SSD losing some contact with motherboard. You need to open the device, get the motherboard out and put 0.5 mm thermal pad on the SSD (under the EMI shield) and put the shield back. Then take a 1mm thermal pad, or 0.5 depending on your preference but I highly recommend a 1mm one to reduce the risk of running into screen fading issue, and put it on the RAM chip. Put everything together and screw the upper screws tight so that pressure is made to the chips.
You can also apply heat to the chip beforehand, while applying some pressure. In that case, I recommend you to put something on the other side, on the RAM chip so that on both chips pressure is made while the heat is being applied. You can use hair dryer but shield the rest of the boad with some aluminum foil. Try only the thermal pads first tho.
more info: https://forum.xda-developers.com/lg-g3/general/g3-hardware-problems-solved-bsod-screen-t3597086

xfim said:
Blue screen is, I think related to SSD losing some contact with motherboard. You need to open the device, get the motherboard out and put 0.5 mm thermal pad on the SSD (under the EMI shield) and put the shield back. Then take a 1mm thermal pad, or 0.5 depending on your preference but I highly recommend a 1mm one to reduce the risk of running into screen fading issue, and put it on the RAM chip. Put everything together and screw the upper screws tight so that pressure is made to the chips.
You can also apply heat to the chip beforehand, while applying some pressure. In that case, I recommend you to put something on the other side, on the RAM chip so that on both chips pressure is made while the heat is being applied. You can use hair dryer but shield the rest of the boad with some aluminum foil. Try only the thermal pads first tho.
more info: https://forum.xda-developers.com/lg-g3/general/g3-hardware-problems-solved-bsod-screen-t3597086
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Hi and thank you for your reply. I hear what you are saying about the SSD but my question is why only very erratically and why only when I do updates? The phone works flawlessly with calls, watching movies, doing email, using WhatApp. The ONLY time I have issues that I can ascertain is when I do updates.

marcd2015 said:
Hi and thank you for your reply. I hear what you are saying about the SSD but my question is why only very erratically and why only when I do updates? The phone works flawlessly with calls, watching movies, doing email, using WhatApp. The ONLY time I have issues that I can ascertain is when I do updates.
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I suppose because updates require a lot of storage I/O so it heats up more and that causes the solder to expand enough to trigger the cracked connection to do its job lol. It also heats up the CPU more than updating system over PC. Thermal pads are cheap. You can, however use aluminum foil just for the test but thermal pads are safer to use.

xfim said:
I suppose because updates require a lot of storage I/O so it heats up more and that causes the solder to expand enough to trigger the cracked connection to do its job lol. It also heats up the CPU more than updating system over PC. Thermal pads are cheap. You can, however use aluminum foil just for the test but thermal pads are safer to use.
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Hi and thanks again for your reply. Well, I can tell you that it is getting worse, I had random reboots and one or two blue screens for no reason, other than just normal usage. I went to the link you provided but the links in that original post to the images no longer work, however I did find the images so just need to ask, what you refer to as the SSD is that the Sandisk 16GB SDIN9DW4 memory as in the image attached?

That is correct. It is an emmc 5.0 spec. Remember to put pressure on both sides of the board (on ssd and ram)

xfim said:
That is correct. It is an emmc 5.0 spec. Remember to put pressure on both sides of the board (on ssd and ram)
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Thanks will do. Now to try to find thermal pads here in South Africa!!! LOL

marcd2015 said:
Thanks will do. Now to try to find thermal pads here in South Africa!!! LOL
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You can try with something else just to test if it works haha. Then you can search for thermal pads. You should be able to find them in a computer shop.

xfim said:
You can try with something else just to test if it works haha. Then you can search for thermal pads. You should be able to find them in a computer shop.
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Thanks I'm sure I will find somewhere. One more question if I may, do I cut the pad to fit the chip or slightly bigger or what is the best tried size for this repair?

marcd2015 said:
Thanks I'm sure I will find somewhere. One more question if I may, do I cut the pad to fit the chip or slightly bigger or what is the best tried size for this repair?
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Yeah you can cut it in the size of the chip but it doesnt really matter as long as it isnt smaller than the chip. If you have aluminum foil at home you can try with that first. Fold it a few times until it's thick enough. Just put some tape over it in case it touches the motherboard so it doesnt short out.

xfim said:
Yeah you can cut it in the size of the chip but it doesnt really matter as long as it isnt smaller than the chip. If you have aluminum foil at home you can try with that first. Fold it a few times until it's thick enough. Just put some tape over it in case it touches the motherboard so it doesnt short out.
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Thanks but I'll rather just do it once right, so I will hunt for the thermal pads. I'm not wanting to disassemble the phone too many times.

marcd2015 said:
Thanks but I'll rather just do it once right, so I will hunt for the thermal pads. I'm not wanting to disassemble the phone too many times.
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Disassembling the G3 is very easy. Check the guide on youtube and you'll get the motherboard out in less than 5 minutes. Just be careful with the ribbon cables. You got two on the bottom and two cameras at the top. I recommend you to try doing this before buying thermal pads just in case I was wrong and the issue is something else.

xfim said:
Disassembling the G3 is very easy. Check the guide on youtube and you'll get the motherboard out in less than 5 minutes. Just be careful with the ribbon cables. You got two on the bottom and two cameras at the top. I recommend you to try doing this before buying thermal pads just in case I was wrong and the issue is something else.
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Will do and thank you for all the help!! I will post an update soon on whether the fix worked!!

Good luck!

xfim said:
Good luck!
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Well it seems there is a deeper issue with this damn phone!! I finally got the thermal pad, Artctic brand, 0.5mm but as soon as i apply the pads to the areas described and tighten up the phone simply refuses to switch on at all!!!. If I remove all screws from the upper frame and then try to switch on it does and blue screens immediately. So I'm thinking I just need to suck it up and get a new motherboard.
Thanks to all for the help with this!
EDIT:
Seems I had to leave it for a while, as it is now switched on and booted up no problem, with pads in place and screwed down. Minor issue now is it won't read the SIM card but I have also found a fix for that. Right now I'm running updates and so far all good, no blue screen yet. Will post back on Monday after I've used it for a bit.

marcd2015 said:
Well it seems there is a deeper issue with this damn phone!! I finally got the thermal pad, Artctic brand, 0.5mm but as soon as i apply the pads to the areas described and tighten up the phone simply refuses to switch on at all!!!. If I remove all screws from the upper frame and then try to switch on it does and blue screens immediately. So I'm thinking I just need to suck it up and get a new motherboard.
Thanks to all for the help with this!
EDIT:
Seems I had to leave it for a while, as it is now switched on and booted up no problem, with pads in place and screwed down. Minor issue now is it won't read the SIM card but I have also found a fix for that. Right now I'm running updates and so far all good, no blue screen yet. Will post back on Monday after I've used it for a bit.
Click to expand...
Click to collapse
If the pads dont work well enough, you can take the motherboard out, remove the metal shields and take some hard flat metal pieces that you can put on both ssd and ram (big enough to cover them), then put some aluminum foil big enough to cover the motherboard (to protect the rest of the board from heat) and take something like pliers to put pressure on both of the metal pieces (aim for the middle of chips). Then take a candle and concentrate heat on both chips. Switch sides every now and then for about 5 minutes. This is how I fixed both reboot and screen fading problem atleast temporarily.

xfim said:
If the pads dont work well enough, you can take the motherboard out, remove the metal shields and take some hard flat metal pieces that you can put on both ssd and ram (big enough to cover them), then put some aluminum foil big enough to cover the motherboard (to protect the rest of the board from heat) and take something like pliers to put pressure on both of the metal pieces (aim for the middle of chips). Then take a candle and concentrate heat on both chips. Switch sides every now and then for about 5 minutes. This is how I fixed both reboot and screen fading problem atleast temporarily.
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Hi, thanks for the reply. No, the pads are working fine, so far, just that I had to loosen the lower screw on the volume/power panel in order to get the SIM card to read. But otherwise so far so good

marcd2015 said:
Hi, thanks for the reply. No, the pads are working fine, so far, just that I had to loosen the lower screw on the volume/power panel in order to get the SIM card to read. But otherwise so far so good
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Good to hear!

xfim said:
Good to hear!
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Hi I would just like to post an update to this,. After much battling I have finally managed to get a working phone that seems stable so far after 4 days. I'm using a 0.5mm pad on either side as the phone simply will not switch on with a 1mm pad on the screen side. Also, I had to screw down the screw I loosened at the bottom of the volume rocker/power assembly, the SIM card is still working however the SD card no longer reads but that's not a serious issue as the phone has 16GB onboard and I'm not using it for major games or movies or anything like that, purely for work email, calls/SMS, WhatsApp.
So here's hoping it will now continue to work and i will post here regularly with any updates and/or issues if that's acceptable to the moderators.

Bare in mind, all of these fixes are not permanent, for a permanent one you need a new MOBO