75
11
MAINTENANCE
■ Fuse replacement
If a fuse blows or the transceiver stops functioning, try
to find the source of the problem, and replace the dam-
aged fuse with a new, rated fuse.
CAUTION:DISCONNECT the DC power cable
from the transceiver when changing a fuse.
The IC-756PRO has 2 types of fuses installed for
transceiver protection.
•DC power cable fuses ................................FGB 30 A
•Circuitry fuse ................................................FGB 5 A
DC POWER CABLE FUSE REPLACEMENT
30 A
fuse
■ Clock backup battery replacement
The transceiver has a lithium backup battery
(CR2032) inside for clock and timer functions. The
usual life of the backup battery is approximately 2
years.
When the backup battery is exhausted, the trans-
ceiver transmits and receives normally but cannot re-
tain the current time.
See p. 77 for battery location.
CIRCUITRY FUSE REPLACEMENT
The 13.8 V DC from the DC power cable is applied to
all units in the IC-756PRO, except for the power am-
plifier, through the circuitry fuse.This fuse is installed
in the PA unit.
q Remove the top cover as shown on p. 73.
w Remove 11 screws from the PA shielding plate,
then remove the plate.
e Replace the circuitry fuse as shown in the diagram
below.
r Replace the PA shielding plate and top cover.
PROBLEM POSSIBLE CAUSE SOLUTION REF.
DISPLAY
The displayed frequency
does not change properly.
•The dial lock function is activated.
•A set mode screen is selected.
•The internal CPU has malfunctioned.
•Push [LOCK] to deactivate the function.
•Push [EXIT] one or more times to exit the set
mode screen.
•Reset the CPU.
p. 6
pgs.
11, 64
p. 22