- Users are reporting a Xiaomi Mi A2 battery life problem in which the phone has only about three or four hours of screen-on-time.
- It appears the problem stems from a bug related to the fingerprint sensor.
- So far, Xiaomi hasn’t responded to the issue, and the official bug report is still marked as “Need more information.”
You aren’t alone on that last point, as many owners are reporting some serious Xiaomi Mi A2 battery life issues. In some cases, users are only getting about three to four hours of screen-on-time before the device needs a charge.
If you visit this thread at Linus Tech Tips, you can follow along as a Mi A2 owner goes over their own trials at attempting to figure out what the problem is. We’ll save you some reading and summarize the situation for you here.
Apparently, the poor battery life stems from a bug that maxes out the eight CPU cores in the Mi A2. Even when the device is sitting idle with barely any processes running, all eight cores are running at maximum speed, which obviously drains the battery very quickly. However, there’s no reason for the cores to run so fast.
While it’s not totally clear how this bug occurs, various users are reporting that it is connected to the rear fingerprint scanner. If you scan your fingerprint to unlock the device, the CPU cores will sometimes run to the max and then don’t stop. The only way to get the cores to work normally is to disable the fingerprint scanner and then restart the phone.
Users report that the workaround of disabling the fingerprint scanner prevents the maxed-out CPU bug, which leads them to conclude that’s where the problem starts.
Although this battery bug is a well-documented issue, Xiaomi has yet to comment on the situation.
Android Authority was tipped on this problem by a Mi A2 owner who provided us with detailed information as well as links to the bug report in the MIUI bug forum and two threads over at XDA Developers. Those threads also have many detailed screenshots and test results that all point to this fingerprint sensor bug being a real problem for Xiaomi Mi A2 battery life.
Xiaomi hasn’t released a statement about the problem and the bug report at the MIUI forum is still marked as “Need more information,” despite being over a month old. We reached out to Xiaomi but didn’t hear back before press time.
Several users have reported returning their phones because of this issue and Xiaomi’s lack of acknowledgment or support.
If you are a Mi A2 owner and facing poor battery life as described in this article, feel free to sound off in the comments.