Andre

Hi I too have this problem. In my case wanted to make a small cluster and shockingly this one is linux capable. Fortunately the original owner broke it just before the new fw came out so may try it with just pcb connected to see what it does.

Same problem here. Maybe worth mentioning but the CMOS battery on these is a small disk with wires attached. I have replaced it (2.6V) but alas no change. It might be worth replacing the 25L16 BIOS IC if all else fails as this has unbricked a few netbooks here. Also check core voltage as if this is too low then it won’t work. Hint: these chips are often used on older netbooks and have a scrapper (Toshiba 630996-001) that has already donated its power switch to the cause. The fiddly part would be flashing this and recommend the chip be wiped twice with zeros to make sure before flashing it with a known good image. You can just buy a chip as well from ze biosman.

Hi, have the same problem (maybe) here. It looks like even using a plastic spudger is enough to do this if you are really unlucky. Incidentally some ideas I had: use “laser soldering” to heat just the prepared solder microcolloid consisting of screened soot/PG dust and solder paste on each end rather than using conventional reflow because this may be far superior. I am looking into writing some papers on this :-) Minimum power may be less than 150mW so a modified BR writer diode could be fine if the board is preheated to 75 Celsius first (still within tolerance) also have some old dead boards with various problems to practise on. Also possible: use IR 250mW diode with coaxial blue beam from weaker laser eg an Osram PL450 as this may be somewhat safer: use indirect viewing via a safe box and other measures to prevent eye exposure to reflected beam(s). Ideally I want to fix the one with long screw damage (found this one in a bin!) Incidentally dried up solder paste is still somewhat useful if chemically separat...

Can this be why some units don't recover after HDMI *AND* IC replacement? I heard that maybe 40% of chips online are fake, some work in 720p only but most do not even run. Fortunately unless you are a complete klutz or used plumbing solder this is repairable, I personally remove chips with Chipquik and extra Fluxite, though pricey it is very efficient. (if you want to make your own the formula is available though not as good) I did find that weighing fake versus genuine is an effective method for these and fake memory cards, the fake will be substantially lighter on a microscale from Ze Finest Greedbay but the cheap ones can be h@x0r3d with some effort. Repeatable measurements to 0.01g and you can see airflow movements! Will share my modification as soon as its complete, had it all apart again to add temperature feedback. Even broken scales are repairable with the right parts from CPC, Farnell, RS, Micro, etc.

Same issue here. A handy tip though is to use DVM on 10A range and undo negative terminal. Meter goes between spade and now exposed negative screw bushing. Monitor current and if charging starts it should draw around 5.1v 1.6A at start dropping down fairly rapidly as voltage builds. Use at own risk, I found that heatshrink around meter probe helps reduce the chance of a short. Pretty sure in my case adaptor went bad as it won't even run my pi!

Hi, I've just taken apart two different failed LED lamps. The typical failure mode on these as the array is normally a 3*8 or similar array and one or more diodes goes high resistance due to overheating or just plain bad design. The series drive chip detects this and shuts down, however sometimes the capacitor goes bad as well. Depending how vigilant your lamp manufacturer was this should just shut down or blow a fuse, but sometimes the circuit goes into runaway and blows all the diodes. I have also seen a similar failure in LED TVs, if you have a dim third of the picture then this is quite likely. Often changing the bad diode (darker than the rest) then testing will bring it back to life. With S**s**g LED TVs the board housing the bad LED can be replaced individually if you can find a scrap panel with good backlight unit(s). LEDs can vary between 3 and 9V Vf which can be determined by voltage testing with a 9V battery and 330 ohm resistor in series, and a voltmeter across diode under test, also handy for col...

HI, have a pair of S3 with broken glass. I did manage to get the glass off a water damaged s4 mini and in the process found that the oled is somewhat transparent once you take the heat spreader off! It's worth noting that if glass ok but display borked then ribbon transplant is possibly feasible. It's very hard but if you have the right tools and nerves of steel...

Yup, had this too. A handy tip is to work under a red safe light or you may have issues with glue prematurely setting. I also found that if you have damaged ribbon cable, once display is off the front glass it can be swapped with a ribbon from a broken led but the alignment is very critical as is placement of z axis tape. The value of the glass especially oled can be substantial even with bad cable! !! There are even sites you can send dead screens and they will recycle the good parts.

Some folks recommend using chipquik (tm) , this does work. Its actually possible to make an equivalent that works slightly better for lead free solder (as used in PS4) and I've done this recently. http://sci-toys.com/scitoys/scitoys/thermo/thermo4.... has one possible formula but the trick is to get the right flux as well.

Usually black screen is cracked LCD glass at the top. Seems these short out and cause the phone to fail startup because the power supply for the backlight (series LED) runs off the same power supply as the screen controller chip, if you take the touchscreen off then you can normally see the damage.

Anyone know where to get the long ribbon cable from? have one where the HDD light blinks when you lightly touch the middle of cable so possibly corroded or otherwise failed. HDD does not boot either, tried trimming 1mm from each end but no effect.

If all else fails I may try metering it and bridge just the single damaged (SATA data?) wire with some modwire.

Hi, yes if the display flashes it might be a loose connection. I’ve also seen similar issues with the foil mentioned, Z axis tape works for reattaching it. The foil used for getting rid of slugs will work as used it before for making patches on antennas etc, but nice Z axis and copper tape is sold with the chibitronics circuit stickers kit.

Note, for folks with damaged foil(s) a suitable replacement is that copper tape sold for deterring slugs.

If you’re careful its possible to overlap it and reattach with 3M Z axis tape.

I did this on an old Huawei with similar problem and it worked fine, also handy for reattaching broken screen flex but its a *lot* harder.

If you have a good glass with bad flex (how?) then this sometimes does work.

Re. dodgy touch screen it can’t be replaced as part of the assembly but can sometimes be worth checking that the secondary flex hasn’t come unplugged from the board: its a PITA to check but if you get it out try cleaning with IPA in case of fingerprints.

If its black, chances are the screen is kaput. About the only way to check is to disconnect the flex for screen, if this is the problem phone should then boot up fine. I saw this on some S6’s once so its quite a common problem.

@pyractor

Hi, is it likely that the touch screen problem can be rectified by replacing the screen?

This one has pretty severe screen burn already but they aren’t cheap.

Yes its repairable as I believe Z- axis tape and a foil patch may work. I have done this on two phones so far and they both worked as it was just a ground in these cases.

Does anyone have the pinout for the front camera please? I want to use the colour sensor (the R/B thing where the IR face sensor transmitter goes) but can't seem to locate these anywhere. I believe this is basically the same as the Sparkfun chip ISL29125 but a different variant.

On mine the camera does not work but before replacing the module ribbon it did still detect proximity so that works fine.

Also found that the S4 mini front camera is very similar alas not identical.

Worth mentioning but I have found that LOCA is hard to get in some locations. A possible substitute at own risk is to use uv nail polish filler and do this under a safe light ie red so you don't let the varnish begin to set. Note that using LOCA where it wasn't before is bad and vice versa.

Hi, have one of these here. How do you tell if it is a bonded screen versus just contact? I don't want to take this apart and make it worse, on this one the OLED is OK (barely) but the glass is smashed beyond recovery so its going to be a tape job for sure.

Also I found that at least for the S4 mini it is actually feasible to use a hair drier and optical reader strip from a dead HP all-in-one printer as this seems to have the right tensile properties to separate the glass on some bonded screens without damaging or scratching the OLED glass. Sometimes if you did scratch it there is a chance of successfully repairing it by replacing the top UV and polarizer layer with some Xylene to break the glue, or simply hope that the LOCA re-bonds everything and fills in the scratches.

Incidentally I am in the market for a Neo mainboard if anyone has a spare, this one has broken power socket.

Maybe just a loose ribbon cable? Worth checking, this one is intermittent and works most of the time...