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I was replacing the DC-In Board connector and when I put everything back I notice the charger light turns ON but turns off when I connected the battery indicator ribbon. The battery is a replacement battery if that makes any difference? (Though this worked fine beforehand) Also there’s nothing showing up at all on screen. I have not screwed in all the screws yet, but would this make a difference? Any help much appreciated

You’ll need to replace the battery checker as it has a short in it (liquid damaged) Unibody MacBook Pro 15" Battery Indicator Board, Apple P/N 922-9033