Timepieces:Education & Repair
Replacing the Quartz Watch Battery
A guide to clean and efficient replacements
by David A. Christianson
When a quartz watch stops keeping time, the immediate assumption is the
battery needs to be replaced. More often than not, that assumption is correct.
Any other problem is less likely because the quartz watch, whether digital
or analog, is an accurate and dependable timekeeper.
When it comes time to replace the battery, here are some things to keep
in mind. A quartz watch consists of a quartz oscillating crystal, an electronic
circuit to drive it, a means of displaying time and a battery to power the
The battery in a quartz watch generally rests in a well with a negative
battery contact strap on the bottom and a positive contract strap on the
side. In some models, the hold-down strap itself acts as the positive contact.
In either case, both straps must be clear of residue. Wiping the straps
with a clean piece of sharpened peg wood (available from jeweler supply
houses) should clean them. If residue persists, use a sharpened typewriter
If the battery is held with a strap and a screw, use a sharp screwdriver
with a blade the width of the screw slot. Don't let it slip and skip across
the watch movement, which would cause serious damage.
If the battery is not held into position with a strap, often it uses
spring tension from a side-mounted contact. In this case, use a small screwdriver,
with the blade biting into the side of the battery and lifting it. Be sure
not to push the side-mounted positive contact down into the battery well.
This positive contact must touch the edge or side of the battery or it won't
Replace with Care
Handle the battery with plastic tweezers (forceps) because oil and salt
from your fingers can have a corrosive effect. If you can't insert the battery
completely with tweezers, use a piece of Rodico or rubber finger cots on
your fingertips. Long finger nails are good for pushing the battery into
Don't touch any part of the watch movement except the battery, its straps
and its screws. And touch these only with tweezers - plastic for the battery
and thin metal tweezers for the screws and retainer strap.
Digital Quartz Watches
In many quartz watches, mainly digital or a combination of analog and digital,
the electronic circuit must be cleared before the battery is changed. This
provision is called an AC - or all-clear - circuit. This is typically a
small silver or gold-colored dot marked AC on the back of the movement.
To clear the circuit before changing the battery, use metal tweezers.
Place one point of the tweezers on the dot and the other on the positive
(+) side of the battery. Or push a spring tab onto the AC dot with a tweezer
tip or probe. In either case, the watch display will likely become blank
and be ready for a battery change. On some models, the display may remain,
but the watch cannot be reset until the AC is cleared.
Quartz Analog Watches
Cleanliness is a primary concern when changing the battery in quartz analog
watches. They use tiny motors that pulse or rotate once per second, causing
the second hand to jump forward one second at a time. Its gears are driven
by such low power the slightest amount of dirt, lint or dried lubricant
will stop the moving parts.
Be vigilant when removing dirt from the case back when opening the watch
to change the battery. This is also the reason the gaskets in quartz watches
must be replaced periodically (see Professional Jeweler,March 1997,
Next Month: Diagnosing Fault, Setting the Watch.
David A. Christianson is a fourth-generation owner of Christianson
Jewelry, Kendallville, IN. He is a director and first vice president of
the American Watchmakers-Clockmakers Institute, a certified master watchmaker
and a fellow of the British Horological Society. Questions, suggestions
and comments on this monthly column may be sent to Professional Jeweler,
1500 Walnut St., Suite 1200, Philadelphia, PA 19102; e-mail askus@ProfessionalJeweler.com.
Copyright © 1998 by Bond Communications.