Furuno FMD3100, Operator'S Manual, Page: 334 / 395

23. MAINTENANCE AND TROUBLESHOOTING
23-2
23.2 Trackball Maintenance
If the cursor moves abnormally, clean the trackball and inside the trackball housing (in-
cluding the lens) as shown below:
1. Turn the retaining ring on the trackball module in the direction of the arrows (see
figure below) to unlock it, then remove the retaining ring.
2. Use cellophane tape to remove the trackball from the trackball housing.
Place the trackball and the retaining ring on a clean, soft cloth laid on a flat sur-
face.
3. Clean the ball with a damp, soft cloth, then use a dry, lint-free cloth to carefully
wipe the ball dry.
4. Use a swab, moistened with water, to carefully clean the inside of the retaining
ring, the inside of the trackball housing, the supports and the lens. Change the
swab regularly so that dirt and dust build-up is easily removed. Use a dry swab to
wipe away moisture.
5. Re-set the ball and retaining ring. Be sure the retaining ring is not inserted re-
versely.
Trackball
Retaining ring
Trackball housing
Supports
Retaining ring - inner side
Swab
Lens