Samsung SM-G981B Repair Manual page 82

3
Attach the back cover and press down on the edges of the back cover.
Check the gap between the back cover and the metal frame.
Before attaching the back cover, make absolutely sure that there are no screws,
miscellaneous parts, or other foreign objects on the inside of the device (among
the battery, PBA, etc.).
If you feel the some gap, remove the back cover and attach it again (some foreign
materials can be inside the device).
Disassembly and Assembly
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