Changing a watch battery yourself is a manageable task that can save both time and money. With the right approach and tools, you can successfully replace a dead battery, restoring your timepiece’s function. This process empowers you to maintain your watch without frequent trips to a jeweler.
Essential Tools and Battery Selection
Gathering the necessary tools and identifying the correct battery is important. Small screwdrivers (flathead and Phillips) are often required for various watch back types. A case opener tool, like a case knife for snap-off backs or a Jaxa wrench for screw-back cases, is essential for opening watch cases. Plastic tweezers are useful for handling the delicate battery without causing damage or short circuits. A magnifying glass can assist with small components, and a soft cloth or mat protects the watch from scratches.
Select the correct replacement battery by checking the old battery’s code. Most batteries have codes like “SR626SW” or “LR44” printed on them. “SR” indicates a silver oxide battery, common for watches and offering stable voltage, while “LR” denotes an alkaline battery. If the code is unreadable, check the watch manual or cross-reference the battery’s diameter and thickness. Reputable brands like Renata, Energizer, or Maxell ensure reliability and longevity.
Opening the Watch Case
Opening the watch case requires precision and the correct tools. Clean the watch exterior to prevent dirt from entering the movement. Place the watch on a soft, stable surface to avoid scratches.
For watches with snap-off backs, a small notch or lip is usually located along the edge where the case back meets the watch body. A case knife or snap-off tool can be inserted into this notch and gently pried to lift the back off. Applying careful leverage is essential to avoid scratching the case or damaging the internal components.
Screw-on backs feature several small screws holding the back in place. These require a precision screwdriver of the appropriate size to carefully remove each screw.
Screw-back or twist-off cases are identifiable by notches around the edge of the case back. A Jaxa wrench or similar adjustable case back wrench is used; its pins align with the notches and rotate counter-clockwise to unscrew the back. Securing the watch in a watch holder provides stability during this step.
Swapping the Battery
Once the watch case is open, locate the battery, which usually appears as a small, round, silver-colored disc. Ground yourself before touching any internal components to prevent electrostatic discharge from damaging the watch’s delicate movement.
To remove the old battery, observe how it is secured. Many watches feature a small metal clip or lever that holds the battery in place. Gently unclip or lift this retainer using plastic tweezers or a small screwdriver, being careful not to bend it or touch other parts of the watch movement.
If there is no clip, gently lift the battery directly out of its compartment. Use plastic or non-metallic tweezers to avoid shorting the battery or leaving conductive skin oils, which can cause corrosion.
Insert the new battery by reversing the removal process. Ensure the new battery matches the old one and is oriented correctly, with the positive (+) side typically facing upwards. Carefully slide the new battery into its compartment, securing any clips or levers that were disengaged. Avoid touching the battery’s surface with bare fingers to maintain optimal conductivity and prevent contamination.
Closing and Final Checks
After replacing the battery, carefully re-seal the watch case. For snap-off backs, align the case back with the watch body, ensuring any specific notches are correct. Press firmly until it clicks securely into place. A watch press tool may be necessary for stubborn backs to apply even pressure for a tight seal.
For screw-on backs, meticulously reinsert and tighten the small screws. With screw-back cases, carefully align the threads and turn the case back clockwise with your fingers until it catches. Then use the Jaxa wrench to tighten it firmly.
Following re-assembly, perform a function test by checking if the watch hands are moving and setting the correct time. This confirms the battery is correctly installed and the watch is operating. A DIY battery change can compromise a watch’s water resistance. The original gasket may be old or damaged, and re-sealing without specialized tools and pressure testing may not restore water-tightness. For watches intended for water exposure, professional re-sealing and pressure testing are recommended to ensure continued water resistance.