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Replaced battery, everything working but first time battery %would not charge past 43%, shut down and came back at 100%, but using it it dropped to 2% quickly but would not die. Subsequent charging will not show it charging but if I power cycle it will show 100%. Left overnight unplugged still shows 100% but 5 minutes of use goes to 2% but can use for hours. Any suggestions?
This sounds like a damaged gas gauge line. Right next to the battery connector there are some tiny (SMD) passive components. One of them insures the continuity of the gas gauge line. This is the line that sends data from the battery to the cpu. It is possible to accidentally pry this component (FL11) off the board while disconnecting and reconnecting the battery. This requires a micro-soldering repair and is not DIY.
