Wow, I'm in the EXACT same boat as you, and I've spent the last week trying to figure it out. I'm at the end of my tether as I've tried a different battery, display, charging flex, and power button flex with no luck. I've also disconnected the front and rear cameras, and faceid dot projector to rule them out...but STILL the phone reboots with an I2C3 display-eeprom error. The history of my customer's iPhone 12 Pro Max was that it was bent on the battery side from a heavy gym weight. The phone was working fine however the display was badly damaged. Amazingly the back glass was undamaged despite being very bent. I replaced the housing with an original pull frame (came with a battery, charging flex, antennas, power flex). I used a V1S to reprogram a new FX5 Soft OLED screen for truetone and I thought I was done! Turns out the customer complained of a bootlooping issue only when charging it. Now, I've gone back to the flex cables and battery from the original phone but the issues persist. I have also resorted...