Chosen Solution
I was trying to replace the swollen battery in my daughter’s iPhone 5s with a recently purchased and functioning iPhone 5c battery. I have replaced batteries and screens on the iPhone 5c devices several times, so I am familiar with the care needed to not damage ribbon cables and connectors during the swap. After replacing the battery though, her iPhone will not charge. I removed the battery and put it back into the iPhone 5c and it charged just fine. Also, when the battery is charged, I was able to sync the iPhone 5s to iTunes and saved a back up of her files, photos and music. I checked all of the connections several times, including the small single wire that plugs in near the battery plug and the plug from the charging port. I do not have a USB Ampmeter to properly test it as I am a DIY type. Any thoughts on what to look for?
Either the charging port is busted or the Tristar chip needs replacement which requires micro-soldering work done on the phone. You can find reputable repair shops that offer a no-fix no-fee model to get them to fix it for you. You can quickly test tristar by unplugging the battery then plugging the charger in and see if it shows apple logo or not, if it does not then the tristar chip is not. Usually I would test another charger port if possible to rule that out.
The 5C battery is not the exact same as the 5S battery even though it does fit. Try ordering a 5S battery and see if that fixes the issue.
