The bottom flex cable, that goes to the main board, if installed backwards, can cause this error. The end with a B on it should be on the bottom board.
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The bottom flex cable, between the bottom and main board, if installed backwards, can cause this error. The end with a B on it should be on the bottom board.
The bottom flex cable, that goes to the main board, if installed backwards, can cause this error. The end with a B on it should be on the bottom board.