Battery service may require reset procedures
Some modules require contact reset or specific handling after a cell change rather than simply dropping in a battery.
Buttons and case seals matter
A functioning module can still be unusable if pushers, contacts or case components fail.
Water resistance is a testing question
A G-Shock’s original rating should not be assumed after opening, gasket deterioration or case damage.
Some modules are better replaced than repaired
Module-level electronic repair is not practical on every model. Parts availability determines the path.