Attention do this at our own risk as it may damage our phone.
My used samsung galaxy pocket-neo was becoming impossible to charge causing me to break the adapter cables with constant wiggling and balancing acts to get it to work. I took it apart and the micro usb socket looked like an extremely difficult soldering job to replace.
The solution I am using for more than a month with no adverse effects is to cut the plug off and strip the 2 power wires at one end of an old usb cable. There are 4 different coloured wires, red, black, green and white. The green and white wires transmit data, whilst the red and black are the power lines. Red is positive, Black is negative. The sleeve of the cable has a metal mesh which is not necessary for my purposes so I electrical taped it back onto the cable.
The next step is to remove the battery of the phone: I have only done this on phones with removeable batteries. The ones I have used have three terminals; one is plus and one minus, the middle one is for a thermistor in the internal of the battery so that it doesn't overheat. Check the plus and minus with a tester to be sure and look at the way it mounts into the phone. The corresponding terminals in the phone are where I connect the wires.
Now here is the complicated part, - or negative(black) goes to the one negative copper pin in the back of the phone. The positive +(red) wire however needs to bridge the other two pins for reasons that I would like to find out. The white and green wire got taped up seperately to avoid short circuits and I replaced the battery to hold the wires firmly in place and closed the back of the phone. Plug the phone into a charger or external power pack (DC 5v) and it will work fine with no overheating, I suggest this be monitored for a while as it may vary with other hardware.
There may be better ways to do this, as far as I can tell in my case I am not actually charging the battery, instead the phone is running directly from the external power source. The strange thing is that the software(CM11) battery icon slowly discharges and after about 10 hours tells me I need to charge the battery but never turns off and when I restart it is immediately back up to full.
I have tested with a normal cable and the micro usb is still working even though it is still only working when I constantly wiggle the cable, I have cleaned it and as far as I can see its not going to ever work properly.
It would be good to know why the battery does not chargewhen using this method. I imagine it has to do with the internal workings of the phone that control the charging, discharging and battery temperature.
Making the old hardware live longer.
Replacing the micro usb is doable with a hot air gun a pair of tweezers, a clunky spring loaded solder sucker, a flux pen and two pairs of 3.5 x magnification reading glasses. You dont need any fancy rework station or microscope, assuming you have steady hands, reasonably good eyesight, and some soldering experience. I just tried this myself yesterday and fixed and Ace 3 and two S3 mini boards from my junk pile, and while it was a little tricky, it didn't require any brain surgery skills, just care, patience and some previous smd soldering experience.
Proceed as follows, mask off all of the surrounding components with kapton tape, apply lots of flux from your flux pen, then heat the plug carefully, pointing the hot air across the plug and away from the rest of the board. Grab the (hot) metal can of the USB plug with the tweezers, and gently lift it. Only remove the plug when all the solder is melted, and it feels loose, to avoid pulling off any tracks. Remove those tracks, and the phone is for the bin. Next, clear any holes that are required to mount the new plug, take care at this stage, as it is imperative that the replacement plug sits flush on the board otherwise the pins on the plug, wont touch the pads on the board, and worse still, you wont get the case back on at the end of the process.
To fit the new socket, clean the pads... no really clean them.... now make sure they are clean, and then flux them and tin them. Fit the new plug, and check that it sits flush to the board. Tack down one metal lug only on the can of the new plug. Check again that the pins are lined up, and carefully drag solder them. Check for shorts. Check again... clean the pads and check again. If you are happy, tack down the remaining three lugs, make sure they are flush and that there are no blobs of solder on the tops of them. Clean the board again. Test... Profit
Total time including additional swearing, re-cleaning... re-re-cleaning and re-fitting.. about 30 minutes and two strong coffees.
The replacement USB plugs are readily available on ebay typically around the £2 ($3) mark, but there are several different styles, and they are different, so make sure you use the correct one for your board.
Now back to your question... why does your battery not charge when you tack the wires to it... simple... it is trying its best not to explode. The USB port provides 5V, but the battery needs between 2.8 and 4.2 vots.. depending on its current state of charge, and this is what the charge controller chip within the phone provides. Anything else and the protection circuit kicks in.
I suggest if you don't fancy repairing the USB plug yourself, you get one of those cheap "universal" usb phone chargers from China, they cost about the same as the replacement USB plug, but are (marginally) less likely to blow up your battery.
itsthatidiotagain said:
Now back to your question... why does your battery not charge when you tack the wires to it... simple... it is trying its best not to explode. The USB port provides 5V, but the battery needs between 2.8 and 4.2 vots.. depending on its current state of charge, and this is what the charge controller chip within the phone provides. Anything else and the protection circuit kicks in.
I suggest if you don't fancy repairing the USB plug yourself, you get one of those cheap "universal" usb phone chargers from China, they cost about the same as the replacement USB plug, but are (marginally) less likely to blow up your battery.
Click to expand...
Click to collapse
Good description of the soldering job, the samsung pocket neo is very small but I look forward to having a go at fixing it properly one day, I dont yet have a magnifying glass or solder sucker, but I want to get them. Without these tools the job would be near impossible.
Little update: the phone is charging, I have disconected it and it holds its charge nicely, the internal software just doesn't register the trickle charge it is recieving, I have loads of old chargers and new usb cables and my old second hand phones micro usb port is way too damaged to work anymore with any charger. I use it as a modem principally, so it is connected every day and providing wifi to multiple devices and has no problems with over heating. Now nearly two months have passed and it works fine. Using this method it is possible to completely remove the battery as well. The phone is running directly off the 5 volt power with no ill effects.
It would be convienient to connect it directly to a pc in usb debug mode occasionally, and this is a very good reason for eventually fixing the usb plug.:good:
I have a VS995 and this replacement battery. I'm getting less than 2 hours of SOT with both Lineage 18.1 offical and the new project lighthouse ROM at less than 50% brightness. I have greenify and ACC installed with magisk as well as no gapps. Any idea how to fix the drain?
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Hello ROMSG,
Can you confirm the battery is drained vs being read as drained? You could try measuring the voltage on battery contacts before and after to confirm.
Or, since this would not hurt, without even confirming, for fun, try and clean out your USB port and the C end of the USB cable with strong alcohol, and then compressed air. Dry for sure - leave it in the sun for a while laying on or right next to some table salt.
Why:
I just finished analyzing a thread with unrelated issue, but there, it seems to me that bad USB port was causing get this: low reading from otherwise good battery (or actually create a drain - dark current on the USB connector itself). No idea why, but must be connected somehow.
I had re-soldered USB port twice in the past and once the power switch on my own devices, so it would not surprise me at all that those internal components would fail. And I am kind of super precise in how insert the cable, just time, I guess.
Funny how things work. Today I received a phone I bought from eBay for $50, because it was "Google FRP Locked". Mint black H918, no water damage. I thought I'd use the LGUP to re-load the software and may-be make it work, or something, you know, for practice learning about this stuff.
Well, it would not boot past the T-Mobile screen. Finally I made it boot to Factory Reset screen, pressed YES and it went black. No more boot, as it reported the battery (which was about 70% full before this) is now at 0%.
From 70% to 0% in a few unsuccessful boot attempts? Wow, that's really something. It did not get hot.. So, where all that energy went? I mean how did it dissipate 11.9 x 0.7 = 8.33 Wh ? It took about 15 minutes if that, so it was dissipating at 4 x 8.33 = 33.32 Wh speed without even getting hot? That's insane.
Anyway, the USB connector looks horrid, and the charge percentage is going ON and OFF when in the USB cable is in it. The USB cable feels loose in the port.
I tried cleaning but it is too far gone. I am going to replace the USB connector with a new one.
But do you see, again, the same link between discharging the battery / bad USB port and boot-loops? If true, this means that there might be a sea of perfectly good phones on eBay, just with bad USB connectors, boot-looping and eating batteries. Re-solder the USB port and you're good to go!
I would be excited to find out what was your result.
Descent2 said:
Funny how things work. Today I received a phone I bought from eBay for $50, because it was "Google FRP Locked". Mint black H918, no water damage. I thought I'd use the LGUP to re-load the software and may-be make it work, or something, you know, for practice learning about this stuff.
Well, it would not boot past the T-Mobile screen. Finally I made it boot to Factory Reset screen, pressed YES and it went black. No more boot, as it reported the battery (which was about 70% full before this) is now at 0%.
From 70% to 0% in a few unsuccessful boot attempts? Wow, that's really something. It did not get hot.. So, where all that energy went? I mean how did it dissipate 11.9 x 0.7 = 8.33 Wh ? It took about 15 minutes if that, so it was dissipating at 4 x 8.33 = 33.32 Wh speed without even getting hot? That's insane.
Anyway, the USB connector looks horrid, and the charge percentage is going ON and OFF when in the USB cable is in it. The USB cable feels loose in the port.
I tried cleaning but it is too far gone. I am going to replace the USB connector with a new one.
But do you see, again, the same link between discharging the battery / bad USB port and boot-loops? If true, this means that there might be a sea of perfectly good phones on eBay, just with bad USB connectors, boot-looping and eating batteries. Re-solder the USB port and you're good to go!
I would be excited to find out what was your result.
Click to expand...
Click to collapse
Lg up typically causes battery drain but not like what you described. Also reflashing wont fix frp in all cases, since the versions of android on these devices is so old frp bypasses are typically a better route. I know from expierence.
LGUP does that? How weird, why? This one is also a bug, most likely.
Thank you for the tips! I had no idea. I just wanted to try different things and see what works. Typically, I'd drop my phone like in a carwash and crack the screen. So, now that I am a little smarter, I try to buy many hardware backup pieces before I need them. So this is essentially an extra screen. But since it works, why not brick it, right? Learn something along the way.
Nevertheless, I need all the hints I can get. Not a pro here by any means. Do you know of any FRP bypass method you thin works good on H918?
Since you're not new to this, would you mind if I start a conversation with you? I need answers to a couple of questions that seem to be omitted everywhere or I can't find where they are discussed.
Also can't wait to find out if you have found the USB port to be the cause of your power drain or if you found it not to be related.
Descent2 said:
LGUP does that? How weird, why? This one is also a bug, most likely.
Thank you for the tips! I had no idea. I just wanted to try different things and see what works. Typically, I'd drop my phone like in a carwash and crack the screen. So, now that I am a little smarter, I try to buy many hardware backup pieces before I need them. So this is essentially an extra screen. But since it works, why not brick it, right? Learn something along the way.
Nevertheless, I need all the hints I can get. Not a pro here by any means. Do you know of any FRP bypass method you thin works good on H918?
Since you're not new to this, would you mind if I start a conversation with you? I need answers to a couple of questions that seem to be omitted everywhere or I can't find where they are discussed.
Also can't wait to find out if you have found the USB port to be the cause of your power drain or if you found it not to be related.
Click to expand...
Click to collapse
What version of android is your h918 on? I'm happy to answer any questions you have.
Hi Guys,
Mine was F800L, and it seems like it have the same problem, bad connector. Even though I unplug the battery, when I plug the charger, it's drain 0.3-0.7 Amps, and it's get hot without turning on.
I am a little scary to desolder the usb port.
Yes xdanubi, replacing the USB port is a tricky deal. I have replaced few USB ports before, and this time I had only two jobs: replace a power switch on one phone and the USB port on H918. I did the power switch soldering job without issues, and I ruined the H918 in my attempt to replace the USB port.
What went wrong:
-My work setup was too low magnification for the H918 job. I should have upgraded to a higher magnification first, but instead I pushed ahead hoping that my sharp eyesight will haul me out as usual.
-I used ChipQuick Low Melt solder paste to mix in with the original solder in order to drop the temperature when removing the port. This was a mistake. The paste produced several independently moving micro solder balls and they run around uninhibited and I did not notice that until too late when I was examining the empty board using high magnification hand held loupe after removing the port. I should have used a Low Temp solder in a metallic form at this stage. That would not create the solder balls. Why didn't I use the metallic low temp solder? I had it at hand! Because the magnification was too low for this job and I did not feel comfortable enough to precisely apply the metallic form. Applying the paste from a syringe is easier when the work area observation is limited.
-I have not washed the board in alcohol prior to starting the job. What this did is even though I have applied the MG Pink Peelable Solder Mask jelly to the area next to repair zone to seal and protect all of the surrounding components, the flux from the solder paste still lifted the peelable mask and allowed the metal balls to run under it to get stuck to some of the smallest components. I should have thoroughly wash/brush the repair area with 97% alcohol and dry before applying the Peelable Solder Mask to have it adhere better.
All in all, I was too confident I can do it because I have done that several times in the past. Things got a lot smaller since then. This USB port on V20 is surrounded by a number of smallest components I have ever seen in SMD, and one needs to have his tools and procedures just right to get thru this. My second H918 is now what i purchased it for - just a bunch of parts.
This doesn't mean you should not try to get it done. Just be aware of particular difficulties, and get your tools, and understand every step of your procedure as you design it and know exactly why you are taking it. Also, some people always seem to get it done just on pure luck, you may just be one of them. I think if you heed my warnings and account for what I did wrong, watch few good videos and practice a little on some dead boards, you'll be all right.
Here are my measurements of power consumption from a working H918 for a comparison:
Battery removed.
Phone is connected to USB charger
Mini screen has a light gray backlight and is clearly separate from the main screen which remains black.
A battery symbol with flashing red question mark is displayed on the main screen
Phone OFF and does not start when I use the power button.
Temperature does nor rise, phone stays cold.
Current: 0.25 - 0.27 A
79% Battery is installed and charged to 85%
Phone is connected to USB charger
Both screens are black.
A battery symbol is displayed on main screen with percentage of charge and green fill.
Phone OFF but will start when I use the power button.
Temperature does nor rise, phone stays cold.
Current: 0.48 -> -> 0.37 A
85% Battery is installed and continuously charged
Phone is connected to USB charger
Both screens are black (power button press is needed to display battery charging percentage)
Phone is OFF
Temperature on power button is 30 C
Phone was OFF but is now started using the power button. Booting.
Both screens are ON
Temperature on power button is 32 C
Current: 0.60 A
Phone is ON and is in Airplane mode.
Both screen are ON
Temperature on power button is 31 C
Current: 0.47 A (Battery is now at 89%)
Hope this helps
I think your current measurements are OK. But your temperature is not OK. Try to see where the heat is coming from? IS it coming from, the CPU (felt on power button) or the USB port? In your case it would not be the battery since it is removed. It should not be the CPU either since the phone hasn't been started. I am not all that clear still on what exactly in the USB area creates the heat. It would be awesome if you could produce an InfraRed picture of the phone with the back cover off while being hot while still OFF without battery and on charger. If you have an access to the IR camera like FLIR. It may not necessarily be the port itself or it's connections. It could be one of those small SMD components next to the port that gone bad, and if that is true, replacing only the port won't help.
Descent2 said:
Here are my measurements of power consumption from a working H918 for a comparison:
Battery removed.
Phone is connected to USB charger
Mini screen has a light gray backlight and is clearly separate from the main screen which remains black.
A battery symbol with flashing red question mark is displayed on the main screen
Phone OFF and does not start when I use the power button.
Temperature does nor rise, phone stays cold.
Current: 0.25 - 0.27 A
79% Battery is installed and charged to 85%
Phone is connected to USB charger
Both screens are black.
A battery symbol is displayed on main screen with percentage of charge and green fill.
Phone OFF but will start when I use the power button.
Temperature does nor rise, phone stays cold.
Current: 0.48 -> -> 0.37 A
85% Battery is installed and continuously charged
Phone is connected to USB charger
Both screens are black (power button press is needed to display battery charging percentage)
Phone is OFF
Temperature on power button is 30 C
Phone was OFF but is now started using the power button. Booting.
Both screens are ON
Temperature on power button is 32 C
Current: 0.60 A
Phone is ON and is in Airplane mode.
Both screen are ON
Temperature on power button is 31 C
Current: 0.47 A (Battery is now at 89%)
Hope this helps
Click to expand...
Click to collapse
Thanks for the reference. Clearly, mine has hardware problems, because even after doing factory reset, the problems persist. Tried to flash the stock pie kdz, still the same result. Without battery, the current drraw arround 0.6A, with battery plugged the phone off around 1.3A, and with phone on can be as high as 1,9A.
One thing that I am still doubt about the problem though, that the usb port still functioning, both for charging and data transfer. But the strange part, when the phone is off, whenever I plugged the usb, the phone boot up, both on PC usb or charger only.
The other strange part was that when the phone got realy hot (I measure 54 with IR gun, and around 60 reading the /sys/class/thermal/thermal_zonexx/temp file, the lower part around usb port keep cool, it is the upper part that get hot.
Descent2 said:
Yes xdanubi, replacing the USB port is a tricky deal. I have replaced few USB ports before, and this time I had only two jobs: replace a power switch on one phone and the USB port on H918. I did the power switch soldering job without issues, and I ruined the H918 in my attempt to replace the USB port.
What went wrong:
-My work setup was too low magnification for the H918 job. I should have upgraded to a higher magnification first, but instead I pushed ahead hoping that my sharp eyesight will haul me out as usual.
-I used ChipQuick Low Melt solder paste to mix in with the original solder in order to drop the temperature when removing the port. This was a mistake. The paste produced several independently moving micro solder balls and they run around uninhibited and I did not notice that until too late when I was examining the empty board using high magnification hand held loupe after removing the port. I should have used a Low Temp solder in a metallic form at this stage. That would not create the solder balls. Why didn't I use the metallic low temp solder? I had it at hand! Because the magnification was too low for this job and I did not feel comfortable enough to precisely apply the metallic form. Applying the paste from a syringe is easier when the work area observation is limited.
-I have not washed the board in alcohol prior to starting the job. What this did is even though I have applied the MG Pink Peelable Solder Mask jelly to the area next to repair zone to seal and protect all of the surrounding components, the flux from the solder paste still lifted the peelable mask and allowed the metal balls to run under it to get stuck to some of the smallest components. I should have thoroughly wash/brush the repair area with 97% alcohol and dry before applying the Peelable Solder Mask to have it adhere better.
All in all, I was too confident I can do it because I have done that several times in the past. Things got a lot smaller since then. This USB port on V20 is surrounded by a number of smallest components I have ever seen in SMD, and one needs to have his tools and procedures just right to get thru this. My second H918 is now what i purchased it for - just a bunch of parts.
This doesn't mean you should not try to get it done. Just be aware of particular difficulties, and get your tools, and understand every step of your procedure as you design it and know exactly why you are taking it. Also, some people always seem to get it done just on pure luck, you may just be one of them. I think if you heed my warnings and account for what I did wrong, watch few good videos and practice a little on some dead boards, you'll be all right.
Click to expand...
Click to collapse
I have a bad eyesight and only have a cheap magnifying glass, so maybe not now. Might as well buy another v20, because the cheapest trinocular still more expensive than that phone.
Descent2 said:
I think your current measurements are OK. But your temperature is not OK. Try to see where the heat is coming from? IS it coming from, the CPU (felt on power button) or the USB port? In your case it would not be the battery since it is removed. It should not be the CPU either since the phone hasn't been started. I am not all that clear still on what exactly in the USB area creates the heat. It would be awesome if you could produce an InfraRed picture of the phone with the back cover off while being hot while still OFF without battery and on charger. If you have an access to the IR camera like FLIR. It may not necessarily be the port itself or it's connections. It could be one of those small SMD components next to the port that gone bad, and if that is true, replacing only the port won't help.
Click to expand...
Click to collapse
Sadly though, I don't have access to any IR cam. I do indeed try cheaper method "ouweee" test like Rossmann did, first using bare finger, then using a some drop of IPA and see where the particular component that dried up first.
As far as I can tell, the below area near charging port were fine. nothing dried up fast in the small component area near simcard, and the small component area under the fingerprint sensor. The one that heated up fast was the most left area covered with shield.
So I don't know weather it's still usb port problems or other hardware problem.
On V20, the CPU is just like on PC, is attached to the board, but touching a metal heatsink (which is the internal frame) with a healp from some pink glob of crappy looking thermo paste. Actually, the CPU itself is covered tightly with a memory chip soldered right on top of the CPU, and the roof of that is sticky-glued to a copper foil, and then that copper foil is covered with the paste glob and that is stuck to the frame.
Few points to note right here:
- the reason that V20 has thermal issues, I think, is due to poor thermal design: three interfaces (CPU --> memory chip --> copper foil --> metal frame heatsink), and each has some less than 100% efficiency in thermal energy conductivity. There might even be a fourth interface if the CPU has a lid, like that on PC, but unlikely so, most probably it's an exposed one like on the graphics cards.
- each of these thermal interfaces has it's own expiration date. At this point in time, you don't know how many of them are expired.
- hardware guys already are doubtful about the goofy looking "thermal solution" paste that is applied between copper film and the frame. How efficient was it to begin with?
- if you had removed the board before, or if you had dropped the phone when this paste was already dried up, it is very likely that it has de-touched from the frame and there is an air gap. Typically this is not how a phone is designed and this is a surprise to some folks.
What ideally needs to be done is the memory chip needs to be removed, the interface conduction layer renewed, and chip needs to be soldered back. Then the renewal needs to be carried out with respect to the second and third interface as well.
Without having to solder anything, you can relatively easily replace / thinker with the second and especially the third interface. The second will require the copper foil to be peeled off. On the phone I ruined, I threw that foil away, intending to go directly from memory chip roof to the frame, but alas, I didn't get to try that. I think that the high efficiency thermal conductive solutions such as liquid metal or diamond pastes are not good here, because there is the reason the LG used the glob of chewing gum it seems - because the interface between the roof of the memory chip and the frame lacks the close tolerance required for a high efficiency conduit to work. Plus the phone has some flex to it, so even if yours happen to be aligned extremely tightly, this would keep changing. For this reason, I think the thermal conduit needs to be a high volume / flexible one, like that again, on the graphics cards. This could be a thick paste or a sticky pad.
The reason they used the copper foil and not a direct connection between the chip and the frame, I think was because the interface between the roof of the memory chip and the copper foil is more precise and is much more flex stable, so, by using a higher efficiency / thinner conduit there they were aiming to help the total efficiency at least a little bit.
I wanted to clean the roof of the memory chip and use some good video card thermal paste / goo / glue / pad directly connecting it to the frame during re-assembly.
I think this is what you can try to do as well. You can leave the copper foil there for now, and try just the third interface. If your results are not significant, then try and remove the foil as well. None of this will require soldering or a high magnification equipment. Just some patience, alcohol, a steady hand and at least a PC experience with the same.
Be careful with the screws. The screws are all different length, and when I opened mine I was following a guidance that there are two groups, but found it to be wrong as my phone seemed to have at least four groups of different screws. It was too late, however, because mine were already mixed within two groups I created. So, I would advise to create a diagram of screw location and keeping track of which screw goes where. I think that many times this phone is taken apart and put together, without this tracking, some screws end up too long for where they were placed and holding parts loosely, thus adding to the flex that might be cracking the older brittle thermal interface.
Frame Thermal Interface Touch Point:
Peeling Off the Copper Foil:
Copper Foil is Removed - Roof of the Memory Exposed :
xdanubi said:
Might as well buy another v20, because the cheapest trinocular still more expensive than that phone.
Click to expand...
Click to collapse
Absolutely. The 20x binocular from AmScope on ebay is around $190. Since Iam only an amateur, I am considering building a DIY usb webcam based microscope like the one EEV blog had reviewed or better. Reading about optics now, - I am an absolute newbie to optics design.
Amazon has this phone "new" for $70 with varying reviews. Might just try that, since on e-bay or Swappa you'd likely get a phone someone from XDA already "worked with" for a while.
I too am baffled with why some phones do turn on spontaneously when charger is connected. From my experience with PCs, this usually indicates:
-- bad BIOS battery
(is there a BIOS battery cell on a phone? Yes, I know there was one on Galaxy, maybe there is one on V20 as well?) This would not generate any heat though.
-- bad corrupted BIOS
(we are on XDA, lol. Should we really try throwing this stone?) But really, maybe a full reflashing should help? I mean a complete, like a full KDZ, not just wiping of data partition which is what a factory reset really is. BUT YOU ALREADY TRIED THIS
-- some dried out capacitors around power on circuits (this one can create heat)
Again, FLIR is needed for this. Or careful thermal probing of SMD components with board being fully connected while outside of the case and plastic housing. Once a hot one is found this could be examined further.
Some research directions here...
xdanubi said:
The one that heated up fast was the most left area covered with shield.
Click to expand...
Click to collapse
Could you show which area was heating up:
xdanubi said:
Without battery, the current draw is around 0.6A, with battery plugged the phone off around 1.3A, and with phone on can be as high as 1,9A.
Click to expand...
Click to collapse
You clearly have about 0.3 A to 0.6 A dark current. Something is consuming this energy and dissipating it into heat. When capacitors are shot they now represent a short on the circuit where there not supposed to be one. Such short will now create this dark current.
Capacitors fail due to old age, high heat (vicious circle), and bad power supplies that deliver spikes and poorly filtered power. Big electrolytic capacitors dry out, explode, leak, but SMD capacitors fail too - they crack and melt.
Code:
https://www.youtube.com/watch?v=IciwMsWX_Y4
There could be other failed components, it's just that capacitors are ubiquitous in this regard.
Descent2 said:
- if you had removed the board before, or if you had dropped the phone when this paste was already dried up, it is very likely that it has de-touched from the frame and there is an air gap. Typically this is not how a phone is designed and this is a surprise to some folks.
Click to expand...
Click to collapse
I do remove the board, to see if there's any clear evidence of burned/short capacitors. And indeed I do have the urge to remove that pinky gummy blob, and ad some PC's cpu paste to it. But the fact that I still feel a good heat to the screen area directly below it, it means that it's still have some good heat conductivity, so I'll leave that to deal with it later.
Descent2 said:
What ideally needs to be done is the memory chip needs to be removed, the interface conduction layer renewed, and chip needs to be soldered back. Then the renewal needs to be carried out with respect to the second and third interface as well.
Click to expand...
Click to collapse
that's one hell of BGA rework.
Descent2 said:
I think this is what you can try to do as well. You can leave the copper foil there for now, and try just the third interface. If your results are not significant, then try and remove the foil as well. None of this will require soldering or a high magnification equipment. Just some patience, alcohol, a steady hand and at least a PC experience with the same.
Click to expand...
Click to collapse
Thank you, I'll do it later after clearing some other problems.