You will need to tear it down. You have shorts in the connectors or cables to the LCD. You may have to go beyond step 34 to actually removing the bezel and possibly the LCD if you can not see cuts/tears on the cables prior to that.
The cables might possibly be repaired with dabs of silicone if the nick is small and not into the wires. You may have to replace the cables if the damage is more severe.
Do not pick the laptop by the display, or force the display to tilt excessively. As you'll see the cables run through the hinges.
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