After replacing the fan, laptop only works when Battery is unplugged
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One of the fans didn’t work, so I bought a new one and tried to replace it myself. After disassembly and reassembly (which was hard enough due to a broken screw), my laptop only works when the battery is unplugged. (Via AC)
When the battery is plugged, I get 3 red blinks next to the power button and nothing happens afterwards.
Both fans seem to work, WIFI, speaker, keyboard worked all.
What happened to the battery? It was in a good state prior to the disassembly.
I appreciate any help. Thanks!
Btw: it’s the lenovo yoga 900-13ISK 80MK (not 13ISK2)