Citizen watches are produced by Shokosha Watch Research Institute, which was founded in Japan in 1918. They are the largest manufacturer of watches in the world. They make a line of eco-friendly watches with a rechargeable battery that lasts up to 10 years. The battery also uses solar power to recharge. Occasionally a battery has to be replaced, and when it does it needs to be reset.
Lay the watch on a flat surface that has a good source of light so you can see everything clearly.
Pry the back off by sliding the screwdriver beneath one of the edges of the watch back, and gently lift the back until it comes off. Move the battery strap to the side.
Slide the tweezers under the bottom of the battery and carefully lift the edge of the battery out of the case. Once the edge is free, lift out the battery and lay it on the side.
Lay the new battery in the case where the old one was and move the battery strap across the new battery to secure it in place.
Push down the battery at the 12 o'clock position and push it in the module mode. Gently depress the battery in the 9 o'clock position and push the springs at the 6 and 8 o'clock positions.
If your watch seems to be slowing down and you have had the same battery for at least five years, it is probably time for a new one.
Use the correct battery as listed in the user's manual to replace the existing battery.