Chosen Solution
Hi there, After I replaced my broken screen, battery started to drain really quickly, it lasts for no more than 3-4 hours with normal use and the battery area gets hot. When on standby it also drains battery much faster than usual. The device is 3 years old and battery health is 87%. I first checked if it was software related by doing a fresh install wiping out the previous installation. No luck. I changed the screen just in case it was faulty but the new screen didn’t change anything. When it is connected to the charger it doesn’t get hot. So I’m suspicious the issue is with the battery… though it’s weird that the battery has gone bad precisely after the screen replacement. I’ve connected a power bank, I guessed that if it was the battery it shouldn’t get hot but it does get hot with the power bank connected. Since it is 4400 mAh it should last for a couple of days minimum. It’s been running for 6 hours now but I have no way to tell if the power bank is depleting faster than usual but wait for a couple of days :-(, it doesn’t look good, the phone gets pretty hot. I’m not a pro but have opened a repaired lots of iPhones in the last 8 years (kind of a hobby…) and I’m lost here. Any suggestions before I change the battery? I don’t want to keep opening and closing the phone until I have replaced every single part but the motherboard… Thank you! Update (04/06/2019) Update: the phone has depleted the a 4400mAh power bank in 12 hours so for the time being I’m ruling out the battery, the screen (quality original replacement) and the front camera which is also original and replaced after the problems started (the second screen didn’t carry its own camera). I´m gonna start disconnecting cables to see if I narrow it down.
Several things can cause Battery Drain issues. You will need to isolate some variables in order to get a better understanding of what is wrong. The problem could be a bad replacement battery, excessive current draw from one of the modular components (camera, button, screen) or it could be a problem on the logic board itself. Here are some things to try: It could be a bad replacement battery; there are lots of cheap batteries on the market. Try replacing with a known-good battery or order a good one from here. You could have excessive current draw from one of the modular components; for example, the backlight, a camera or a sensor. You may notice a hot spot on the phone or screen. Fully charge the battery first.Disconnect the battery and then disconnect one modular component at a time to see if you can determine which part is bad. I would start with the front camera flex, then the rear camera, then home button. If that doesn’t make a difference, then you should try to disconnect the screen to see if it’s the screen or the logic board Disconnect the battery, then disconnect the flexes for the screen assembly, buttons and cameras, leaving only the Lightning Dock connected to the logic board (follow these guides). When you are done, re-connect the battery.Go back after an hour or more and test the condition of the battery. You will need to download either coconutBattery (Mac) or 3uTools (Windows) to see the battery condition.It could also be the Lightning port so you could try the same test as above but with the Lightning port disconnected once the battery is charged (connect it back to test the condition of the battery). You may have a damaged logic board. This will require a micro-soldering repair and is not DIY. Drops, bends, water damage or using poor quality charging bricks and cables, can cause this.
