Samsung SM-A500H disassembly and reassembly manual in PDF, 739 KB. It documents the order of removing the rear cover, frame, battery, main board and flex cables, with the reverse steps for refitting. This is a mechanical guide, not a circuit diagram, so pair it with the SM-A500H schematics when diagnosing power or signal faults. Taking parts out in the documented sequence avoids broken clips and damaged connectors. Make sure the model code on the device matches, as other A500 variants use different boards.
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