Furuno FCV-1100L - Manual (Page 68)

5. MAINTENANCE, TROUBLESHOOTING
5-4
5.4.1 Panel Test
The “panel window” at the bottom of the diagnostics display is used to check
keys and controls.
1. Press any key except the [PWR] key. The pressed key’s on-screen location
changes from 0 to 1 when the key is pressed.
2. Operate each control. The figure on the screen changes as below.
[FUNCTION]: 1 to 8
[RANGE]:
0 to 20
[MODE]: 1 to 7
[GAIN]: 0 to 255
3. To quit the diagnostic test, press the [MARKER/TLL] key more than three
seconds to return to the SYSTEM menu, then rotate the FUNCTION switch
fully counterclockwise to select EXIT.