[Xiaomi Mi Max Questions & Answers] scort02:
Mimax Helium Random Shutdown at 80+% Battery Charge

My phone shuts down randomly on a full charge and it all began when I sat down with the phone in my back pocket. The case curved and it just began behaving badly.

I bought a new aluminium back from eBay and power button ribbon because it did not power on when pressed many times. This did not help much, but it was cool have a straight shiny new case and fully functioning power button.

Annoyed, I took the phine apart and realized that the battery ribbon was coming loos whenever the phone was bumped ever so slightly because the battery was moving around in the phone. Furthermore, the screws holding the metallic plate over the main board had thread out. Thus, it's was not holding the ribbon in place. Note, you will know that it is a poor battery to main board connection problem if you apply pressure connection and the phone start when the power button is pressed and dies as soon as the pressure is released.

To fixed the threaded out screws, I place a dab of crazy glue into each screw hole. To apply pressure on the battery to main circuit boards ribbon connection, precut a small piece of cardboard and attach it to the back of the battery ribbon where it attached to the main board with a speck of crazy glue to hold it in place. Then quickly replace the metallic plate on to the main board with the screws before the crazy glue in the screw holes dry completely.

To keep the battery from moving around in the phone I placed a speck of glue from my hot glue gun on perimeter of the battery to secure it in place. I then realized assembeled the phone and gave it a full charge.

Realizing that the problem could also be related to an outdated rom, I downloaded the latest rom and flashed it. Then, I came across a firmware update project on xda at https://www.google.com/amp/s/xdaforums.com/mi-max/development/firmware-xiaomi-mi-max-t3741655/amp/ so I flashed that on to the phone too.

As of this posting, the phone has been running without issue for the past 48hrs. Hope this helps, because I was actually dreaming about smashing this phone with a hammer. Now I love it again ?

---------- Post added at 11:16 PM ---------- Previous post was at 11:08 PM ----------

My phone shuts down randomly on a full charge and it all began when I sat down with the phone in my back pocket. The case curved and it just began behaving badly.

I bought a new aluminium back from eBay and power button ribbon because it did not power on when pressed many times. This did not help much, but it was cool having a straight shiny new case and fully functioning power button.

Annoyed, I took the phone apart and realized that the battery ribbon was coming loos whenever the phone was bumped ever so slightly because the battery was moving around in the phone. Furthermore, the screws holding the metallic plate over the main board had thread out. Thus, it's was not holding the ribbon in place. Note, you will know that it is a poor battery to main board connection problem if you apply pressure to the connection and the phone starts when the power button is pressed and dies as soon as the pressure is released.

To fixed the threaded out screws, I place a dab of crazy glue into each screw hole. To apply pressure on the battery to main circuit boards ribbon connection, precut a small piece of cardboard and attach it to the back of the battery ribbon where it attached to the main board with a speck of crazy glue to hold it in place. Then quickly replace the metallic plate on to the main board with the screws before the crazy glue in the screw holes dry completely.

To keep the battery from moving around in the phone I placed a speck of glue from my hot glue gun on perimeter of the battery to secure it in place. I then reassembeled the phone and gave it a full charge.

Realizing that the problem could also be related to an outdated rom, I downloaded the latest rom and flashed it. Then, I came across a firmware update project on xda at https://www.google.com/amp/s/xdaforums.com/mi-max/development/firmware-xiaomi-mi-max-t3741655/amp/ so I flashed that on to the phone too.

As of this posting, the phone has been running without issue for the past 48hrs. Hope this helps, because I was actually dreaming about smashing this phone with a hammer. Now I love it again ?