76
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-756PROII 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. 78 for battery location.
CR2032
CIRCUITRYFUSE REPLACEMENT
The 13.8 V DC from the DC power cable is applied to
all units in the IC-756PROII, except for the power am-
plifier, through the circuitry fuse. This fuse is installed
in the PAunit.
qRemove the top cover as shown on p. 74.
wRemove 11 screws from the PAshielding plate,
then remove the plate.
eReplace the circuitry fuse as shown in the diagram
below.
rReplace the PAshielding plate and top cover.
Circuitry fuse (FGB 5 A)
PROBLEM POSSIBLE CAUSE SOLUTION REF.
DISPLAY
The displayed frequency
does not change properly.
•The dial lock function is activated.
•Aset mode screen is selected.
•The internal CPU has malfunctioned.
•Push [LOCK/SPEECH] to turn the function OFF.
•Push [EXIT/SET] several times to exit the set
mode screen.
•Reset the CPU.
p. 46
pgs. 11,
64
p.21