Chosen Solution
replace the battery but still does not charge
@welch290 … no charging indicates 3 possible causes. no current from the ac adapter, bad/damaged cell battery or a bad/faulty charging ic chip on the motherboard. the only way to test these and diagnose properly is with a multimeter. starting with the easiest, test the output of the ac adapter for voltage. https://itp.nyu.edu/physcomp/lessons/ele… next, check your batteries voltage. https://www.youtube.com/watch?v=-MGQ0Ap_… finally, open up the device and test for voltage from the charging port and then also the connector at the battery on the motherboard. to do this, youll want to have a schematic for the voltages that are supposed to be present, but not necessary to get an idea if its functional. being that this is a mac, please post your model number a****? you could also try to reset the pram and smc first if the battery was properly diagnosed. https://support.apple.com/en-us/HT201295 with these tests, youll know exactly where the problem lies and how to correct it. you can use google/ youtube to learn how to do these tests, or post back here with any questions you may have.
Sadly the 13” & 15” Touch Bar both face the same issue which Louis goes over here A1707 Macbook Pro touchbar no power failed logic board PP3V3_G3H issue
