I am having this issue in December 2022. Replaced battery with SP4 version from iFixit. Replacement measures 7.34V. Control board doesn’t line up as nicely as the original but it technically fits into the pins. Checked for bent MB contacts, but nothing stands out. MB fully seated making good contact with battery pad. No power on when using battery only, or when plugged in. Surface dock lights up solid, as if achieving good communication with battery board. Checked the two shotkey diodes and 000 “fuse” near CPU. Ensured everything plugged back in and seated properly. No visible damage anywhere.
Any other ideas? Has anyone had any success with this repair?