Might have water damage but power is off and won't turn on

Shortcut battery with AC contact. AC can be found on the sides of watch movement(very tiny). You have to use pointed tweezers: one end on battery+, another on AC contact for three secs..

You need a tool like this. Be aware if you open the watch it won't be water tight and can't be used under water again. Even a jeweller can do the damage to your watch. To keep it water tight you should go to or send it to a Casio certified repair centre.

I have a different model but this solution came up in Google and it didn't work. On mine, I tried the following: press MODE. It will show the alarm time. Then press ST/SP a few times until the little alarm icon does not show on the alarm face. If you press RESET instead of ST/SP, it will start blinking and will want you to change the alarm time instead.

check the caseback of your watch, hold it upright turn it around. look at the markings, if the markings is doesnt match the upright postion you have to open it then put the caseback on its proper position because the part that is beeps is attached on the caseback and the machine has small spring to connect power on it. i hope i had been helped you.

It's a 395 (SR 927 SW), however you're going to need a case wrench and a 4-pin vise to get the back off so you're looking at a minimum of $40 for the battery and the tools and that's if you know where to look. The other problem is the rubber gasket which may need to be replaced as well. Unless you happen to have a supply of them handy for that exact size case, your watch will no longer be water resistant to the manufacturers specifications. You could probably wash your hands with it but I wouldn't recommend anything more intense. The problem that you have is that you won't know if you need a new gasket until you get the case open and as noted, that's cost you a minimum of $40 to find out and you get the pleasure of having a set of tools that you'll probably never use again. Or, you could save yourself the money, headache and aggravation and of course the high probability of you damaging it because you lack the experience to change the battery on a screw-back, water resistant timepiece and just take it to a local jeweler, pay $10 - $15 to professionals who know what they are doing and will include the replacing of the gasket at no extra charge.
A universal Screw-Back (what your watch has) Watch and a Case Wrench

A 4-Pin Vise