Postagem original de: Rany ,
@hoshi, like aqi said, first you must check that your charging dock is clean, not corroded. Next step is to try a known good one instead. No need to replace it at this point, just overlay it the existing one and plug it instead of the old one and test with a known good cable and charger - or computer. If the phone still doesn't connect via USB, you probably have a bad U2 chip. It is a controller chip responsible for USB communication and charging. It is a very common failure on iPhone 5. If you want to be "extra sure," you can examine around the battery and dock connector to see if you see anything missing or damaged. Your friend could also have shorted something when disconnecting the old battery, if using a screwdriver for example to lift the battery connector. That would hardly be visible to the naked eye though. You can also try installing a known good battery (not necessarily new) that is already holding a charge. If it depletes quickly and/or phone produces heat between the CPU and SIM card tray and/or still doesn't communicate with your computer and/or won't charge anymore once empty then for sure you have a defective U2 (google it) that requires micro soldering skills and tools to repair. Definitely not a DIY repair.