Need to replace battery in my casio 593 wristwatch
Old question, but I just had to do this, so posting for anyone else's benefit:
1. Remove and keep safe the 4 small screws at the corners on the back
2. Carefully remove the back, ensuring the black seal stays in place ideally attached to the back.
3. The battery is partly visible under the metal cover. Remove the whole assembly from the case of the watch, remembering which way round it goes
4. Using a very small flathead screwdriver or similar, lever the 4 clips on the metal cover gently away from white plastic body and up, one at a time, working round until the metal cover is loose. You may need to go round a few times. Remember which way round it goes.
5. The battery is held in place with a sticky pad. Don't pull it, or the display will come loose. Gently lever it away from the green circuit board.
6. When the battery is loose, if the sticky pad is on the battery remove and reattach to the circuit board just inside the circle where the battery sits.
7. Stick the new battery down, plus side(with writing on) towards you. Be careful not to touch with your hands to maximise battery life (eg use a PVC glove)
8. Insert the assembly back in the case, battery upwards, the same way round. Lower the metal cover back over the battery, ensuring it covers the battery not the springy clip protruding from the circuit board. Align the 4 clips with the gaps they fitted in before and press into place in all 4 points.
9. The watch should now show a working display. If the light doesn't work, the battery is not in correctly. If the display is showing random rubbish, it probably came loose. Try carefully easing the circuit board one way or the other in the white body to realign it, but if this fails, remove the metal cover and remove the circuit board from the white cover, replace both, and try again.
10. Replace the back taking care to put the seal in place and replace the 4 screws. Set the time according to the manual. It will tick for about 5 minutes, and show a dot to the left of the day abbreviation. No idea why. It stops after a while.