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You didn't specify if machine starts with battery alone (no charger).
Also good to know exact PPBUS_G3H voltage without battery (only charger connected).
Just in case, change Q7155.
12.6V is the expected voltage; you might got 12.4V at incorrect test point.
That's the reason of above explanation.
Post SMC_CHGR_BMON_ISENSE and SMC_DCIN_ISENSE levels, with both charger and battery connected.
Also check if machine stays on (no restart) in SMC bypass mode.
Did you test with known good battery?
Keep in mind "new" (chinese, or not), is not the same as known good!
I hope this "How to" collection will help our members. I will possibly modify this post in time, if updates available. Trigger SMC_ONOFF_L (PMU_ONOFF_L): It reffers to simulate power button function, when the keyboard is not connected. We need to do this when we work with the board...