Water damaged iPhone data recovery is no simple task, so it can be a scary experience to drop your iPhone into water. What's worse, it can be downright devastating to drop your phone from a harbor into the ocean. This is what happened to Cassaundra De La Rosa from Cypress, CA. The last 2 years of her life had been largely only documented on that phone and she was not willing to just let those photos go. Luckily, she contacted us at iBoard Repair to help with her iPhone Data Recovery. If you need help with your iPhone data recovery, fill out the intake form here.
Contrary to popular belief, iPhones are not water proof. They are only water resistant and that resistance is only effective up to a certain depth while the phone is still relatively new; it degrades with age.
For years, the standard practice for data recovery had been to use "chip off" methods to access the contents of the NAND (also known as memory) chip by desoldering it and placing it into a jig or socket to directly extract the files. This method was widely used because it was straight forward and formulaic. However, iPhone data recovery is drastically different. Apple's end-to-end encryption makes it impossible to use these sockets and readers to access the contents of the memory chip. Before the data can be decrypted, the NAND must check in with the CPU and the EEPROM chip as well as receiving a user "trust" by way of entering a passcode on a working iPhone screen.
This means that they way to data lies in advanced hardware repair down to a micro level. The phone must boot, the usb port must function, the image must function, and the touchscreen must function.
When we received this message, we knew we were in for a challenge:
When our technicians opened the phone, it was not a pretty sight to see. Corrosion lined the frame of the phone and the flex cables had already started to deteriorate from the salt water damage. This is not a problem in and of itself, as all of these parts can be swapped out with working ones.
Water damage inside your iPhone
The iPhone XS has two motherboards that are soldered together around the perimeter via an interposer. Apple started using this design to save space within the phone and make room for a bigger and longer lasting battery. However, this makes getting to the "guts" of the phone much more difficult. The solder pads connecting these two motherboards are composed of low melt solder (148 degrees Celsius). This means that a heating platform can be used to raise the temperature of the entire motherboard unit to around 150 degrees Celsius and only these pads will become pliable while all other solder connections remain firm.
After splitting the two layers of the motherboards we can see the innermost components and it is clear that corrosion is very widespread. Note the low melt solder pads around the perimeter and the crusty looking corrosion in the next two pictures. Not only does this corrosion effect functionality of the individual chips themselves, but it often bridges power lines or disrupts i2c communication protocols to the CPU, causing immediate power failure.
Water Damaged Motherboard
The section pictured below is home to two camera LDO chips, their power boosting coils, and further right are the audio amplifier chips. The corrosion under and around these chips were causing the main power line (VDD_MAIN) and the main boost line (VDD_BOOST) to become shorted to ground, dumping all voltage into ground instead of the lines they are supposed to power. Along with that, i2c and other communication lines were also disrupted which causes the CPU to lock up. The voltage actually burnt a hole into the motherboard itself, shorting vdd_main and requiring a razor blade to dig out the bridge. These chips just allow the camera and the audio functions of the phone to work, however they do not need to be there to allow the phone to boot up. Because of this, it is best practice to simply clear out the chips and their corrosion to get rid of any of the problems they were causing.
Motherboard Repair and Cleanup
Below is pictured the yangtzee chip and it is part of the charging circuit. It is needed to allow the battery voltage to reach the main power line. Without it, VDD_MAIN can not have access to its power source; the battery. Without power, the motherboard will not turn on. Because of this, the chip is removed, the corrosion is cleaned and the solder reflowed, and the chip is replaced with a new, working chip.
An Essential Motherboard Chip
After that work and some more general corrosion cleanup the phone would turn on, however it would restart after just a couple minutes, making it impossible to get a full backup. It was also noted that the phone would show low battery even though we knew the battery was full. This points to the battery data lines not being read by the CPU. When the CPU cannot read how much voltage the battery has, it shuts down after a few minutes as a precaution as it does not know if it is overflowing and at a risk of blowing up. It was tricky because not only were the mosfets that read the battery voltage bad, but the pins on the fpc connector that connect the battery to the motherboard were also not making contact:
Components that read the battery percentage
Motherboard work after water damage is very finicky and things can go wrong at any moment. After fixing the battery data problems, to our dismay we see that the phone appears to not turn on. This is not good! We connect the motherboard to an external DC power supply so we can check the amperage draw and see if we can recognize the boot sequence from the power draw. By knowing what an iPhone's DC power signature looks like, we can see that it does in fact appear the board is booting. This means that image must have gone out. This was also tricky because voltage drop (diode mode) on the OLED fpc was normal, and the image power rails were also turning on. Eventually, the image data chokes were replaced for good measure and we found that one of them had been bridged, causing a communication problem to the CPU. Diode mode did not show this because they were already supposed to have the same value. The two points below had a bridge that could not be seen until the component was removed:
iPhone Screen Shows No Image
Once that is corrected, we put the phone into a jig that connects a known good bottom motherboard to the top one. We do this as a way of quickly removing any problems associated with the bottom motherboard as the top motherboard is the one that contains all the necessary decryption components. This allows any potential bottom motherboard problems to be taken care of in one easy step (the only easy step in the process), and also allows the proper i2c and other functions (touch is powered by the bottom board) to operate. What this means in practice is that we only need to diagnose and repair the top motherboard and can simply switch out the bottom one. Once it is in the jig, we can see the phone boots up and we have access to the user data.
iPhone Motherboard Inside A Jig
Here you can see the top and bottom motherboard side by side:
iPhone X Motherboard
The job is a success and the is nightmare over. Our customer couldn't be happier to have her photos back of her children and vacations.