@grxceritz use this disassembly guide [guide|139759] to get to the battery. Replace the battery and re-evaluate. Let us know if this fixed it.
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@grxceritz use this disassembly guide [guide|139759] or check [https://www.youtube.com/watch?v=ZRqQyHwuN4U |this video] to get to the battery. Replace the battery and re-evaluate. Let us know if this fixed it.