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Cooking with the Nexus 5X

My LG Nexus 5X lasted around 2.5 years before it was hit by the infamous boot loop issue. This basically means that the phone reboots constantly and it is impossible to even get to the OS. Luckily, all the data is in the cloud, so I can just buy a new phone and continue using it like nothing happened. Yeah... not really.

One of the apps I thought was backed up was WhatsApp. It does have a backup function that uses Google Drive, but I had it set to a 1 week interval and the phone died just before next the backup was about to be made. I was not going to lose a week's worth of (bad) memes! There were also some other apps like Nordea Codes that would've made my life much easier if I were to gain access to them before getting a new phone.

So, this is the story of how I (almost) fixed my phone.

I knew about the boot loop even before my phone died. Other people had success in fixing it by baking their phones in the oven. I didn't like the possibility of literally frying my phone, so I wanted to try out some less scary first.

Freezing the phone

This is an old trick used to recover data from HDDs, and I thought it was quite safe if condensation water was kept out.

The process:

  1. Put the phone in an airtight bag
  2. Put the bag in a freezer
  3. Take the phone out when the temperature has settled
  4. Boot the phone and recover the data

This method didn't yield much success, and I wasn't able to get it to boot to the OS. Maybe the CPU warmed up during boot so fast it didn't stay cold long enough. The why will probably remain a mystery.

Baking the whole phone

Okay, so cold did not work. How about hot?

The process:

  1. Pre-heat the oven to 50°C
  2. Put the phone in the oven
  3. Take the phone out when the temperature has settled (maybe ~15mins)
  4. Boot the phone and recover the data

Baking the phone did in fact work, but only temporarily. I was able to get it to boot into the OS, but as soon as I started backing up anything the phone rebooted once again. 50°C is a bit over the optimal operating temperature of a lithium-ion battery, so I was slightly worried about leaving the phone in the oven for too long. Maybe it would've worked better if cooked for longer.

Baking the logic board only

This is the one I had the most hopes with. Baking electronics has been used in resurrecting dead graphics card and motherboards, and there were believable reports on the web that some had successfully used this method with their boot-looping phones. I decided to follow the example of one of the success stories and set the target to 6.5 minutes at 200°C.

Let's get disassembling.

Step 1: Remove the back cover

The cover is held in place using clips, so use a plastic wedge to make an opening between the back cover and the frame. Then just go around the cover with the wedge and pull it apart.

The back cover removed

Step 2: Detach the midframe

The midframe comes off in two pieces: the bigger one containing the fingerprint reader and a smaller bottom half. The pieces are held in place with phillips screws and clips. Unscrew the screws first, and then unclip the frame while pulling it off.

Detaching the midframe
Bigger plastic components detached

Step 3: Detach the battery

Disconnect the battery connector from the logic board. The battery is glued to the frame and it cannot be just pulled out. I used a wedge, but the glue was stickier than expected and I was not able to get it out 100% undamaged. The battery did bend slightly, but at least there was no smoke 😅.

Step 4: Detach the logic board from the frame

Disconnect the front-facing camera from the logic board. There shouldn't be any screws left, so the board should separate easily.

The logic board and battery taken out

Step 5: Baking

Okay, we're getting to the beef of this story. Set the oven temperature to 200°C, and while it's warming up lets prepare the baking tray.

Take some aluminum foil and make a ball out of it. Straighten it back to a sheet and lay it down to a baking tray. Place the logic board on top of the foil.

The logic board on a baking tray

Place the tray into the oven and set a timer to 6.5 minutes.

Exciting!

When the time is up remove the tray from the oven and let it cool completely.

Step 6: Assembly

Just follow the steps 1-5 in reverse order. You might want to leave the back cover off just in case.

Result

After a quick assembly, I hooked the phone to a charger and tada - it booted up!

It's alive!

I was able to backup everything, and I even ditched my temporary phone. The joy was a bit premature though, as the fix only worked for a few days before reverting back to it's former self.

Looking back, I could have installed the boot loop software fix after I backed up everything to work around this issue completely. The downside is that it would've required the phone to be unlocked which mine wasn't, and I would've liked to keep it that way. Ultimately I decided to switch to a Nokia 6.1, but that's another story.