There seems to be a growing number of Pixel 4 & 4 XL users who are experiencing the very same issue. Symptoms like
- Phone stuck on 50% battery
- Random restarts
- Issues charging
- Battery icon with a question mark inside it.
- Eventually the phone just stops charging completely and briefly flashes a red battery icon.
I first noticed this issue on my own device. Then, after a bit of online research I noticed I wasn’t alone. You only have to type “Google Pixel 50% battery” into google to see the hundreds of articles or thousands of users experiencing the same thing. As seen here, here, here, & here, even googles own support forums. But nobody is really explaining what the cause of the issue is. Everyone just wants a simple “DIY” fix. Unfortunately for everyone, there isnt one. The phone needs to be repaired by a professional.
Google is however covering the issue under warranty. (which you can organise via chat, by logging into your google account, and visiting here).
The issue is caused by fracturing of the Battery FPC connector, which results in the phone not recieving data from the battery. Li-Ion batteries in modern smart phones don’t just have a ‘positive’ and ‘negative’ terminal like your more simple batteries. They also transmit data to the phone. Which consists of telling the phone the temperature of the battery, the amount of cycles its completed, its current voltage, and more.
However when this data isn’t getting transmitted to the phone – yes there still is power to the phone – however the phone cant determine what % the battery is. The battery connector on the battery side, doesn’t have much solder on it, and fractures quite easily after a drop.
Your phone needs to have the battery itself replaced, aswell as you need a microscope to remove the male connector of the battery terminal from inside the female connector ( board side ) without damaging the connectors. As replacements for these connectors seem very hard to locate.