Hey guys! How are you? Edgar here welcoming you all one more time
that's right, with another video
in this video we will see a fault that I've already diagnosed
the video is done, but I'm just presenting the problem so that we can understand it
this is an iPhone 11, this phone
was repaired in a Live that we did a few days ago
this phone didn't turn on
this phone couldn't turn on due to a short on a main line
on the VDD_BOOST line
so, we removed the capacitor, the phone turned on and I said "Well, that's it" and put it aside
then in the afternoon, when I had finished all the work, I had to assemble the device
my surprise was that when I plugged in the phone, it turned on and started charging
but the percentage did not go up
so what I did was
connect it to the computer
whenever you have a phone that doesn't charge or the percentage goes up
it's important to know if the phone recognizes the battery
I started 3uTools and it didn't recognize the battery
this is a common problem
is often due to the pins in the center of the battery not making contact
if someone change the display probably removed a transistor
and that's why the line doesn't have communication
and it's a fault we've already seen in previous models
from iPhone 8 onwards, those lines are controlled by I2C
on the battery pins, there are two pins in the center, the thinner ones, have I2C lines
remember, I2C has two lines, Data and Clock
in this case, the lines come from the CPU
so, what I did was
measure the voltage drop, I checked and confirmed that the pins are making contact
so I had to measure the voltage drop
and the surprise was that I found
the Clock line in short circuit
that line just runs from the battery connector
we'll see that in the video
passes through a resistor and then goes to the CPU
removed the resistor, measured from the side of CPU
and the short was still there
so, what we have to do?
We have to remove the CPU reball it
and see if the short is gone
So, that's what we're going to do in this video, let's see if we can repair it
now let's see the video
(here play some pretty music)
(and put the video in fast motion)
Ok then, we have just removed the CPU, here you can see some spheres
from the CPU, we've already removed it
but
sadly, this motherboard, if we see here
we can see that
the short is still there
Right? The short is still there, if you noticed when I was working with the CPU, I checked
the short was gone, so it is not a short between layers
not that this is a transplant solution
but this is still in short, so this tells me
the CPU is the problem
here I have
the phone, let's
connect this
here
and now turn on the device
let's see if it turns on
Ok, I think it will turn on there
let's wait a moment for the phone to turn on, basically this phone
everything will work, except...
remember, I am only using the upper part, not the lower part
but this phone works perfectly, it just doesn't recognize the battery
if it doesn't recognizes the battery, it will not charge
now the phone is on
912091 is the code
let's see if it works, I don't think it will
because it doesn't have the lower part, 912091
912091
let's
let's turn it off and
check with the lower part
let's put it here
so it can turn on normally without problems
this phone as I told you, it was sent off, I was able to recover the data
but I can't get the phone to work at 100%
let's move to the microscope because I need to turn it on
and
to turn it on
I have to touch these two
now it will turn on
let's turn it around, there it is turning on
very carefully
we have to wait for it to finish turning on
Okay
912091
there it is
we can see that everything is working, Wi-Fi
this from here
IMEI, everything is working
the only problem is
it will not recognize the battery, because
as we have already seen, let's move back here
to the microscope
this line that goes to CPU is in short
there is the short, so, sadly this phone cannot be repaired
as we saw in the video
"Edgar, why don't you do a transplant and move it to another motherboard?"
Nope, that doesn't fix the problem
if you noticed, when I removed the CPU
I measured the line
and there was no short
that means the board is fine
the whole process of the CPU was done correctly
in fact, the phone turns on, the cameras work, Face ID works
signal, everything
but this phone will not work for the simple fact that it has a short
in the Clock line detecting the battery
look what a problem this is
I've talked to other colleagues and they have told me that they have already had the same problem
where it is disconnected and comes from the CPU
the CPU is damaged, leaking or short-circuited, as in my case
this is an annoying problem, does Apple know about this problem?
Because we can say that these are "mini faults in series" in these models
this is a pretty bad problem because
is literally unsolvable, we can't take and program another CPU
we can't put another Clock on it, that's not going to work
so, sadly, this phone can't be repaired
but I hope we can learn something today
#1
Measure, the battery didn't detect it
with 3uTools
measured, found the problem, looked for it and done
and #2
learn the process of how to remove the CPU
how to clean it, how to reball it
and how to put it back
the whole process was perfect
because the phone did turn on without problems
I will probably bring a more detailed video later
about CPU, reballing and all
so that we can learn about these advanced techniques
For me, it was a pleasure to bring you this content
very...
sad, because this phone couldn't be repaired
it would have been a pretty repair if it worked
but sadly it was not the case
not everything is possible, we have to learn to go to the last end and see if we can fix it
or just rest
So guys, it was a big pleasure
to come and say hello to all of you, don't forget to subscribe to the channel
follow me in my social media, we upload a lot of content there
and we'll see you
I don't know why I always hit the desk...
in the next video!
Bye!