REV.-A
Table 5-5.
Board Unit Repair
Problem
The printer does
not operate at all.
(The power lamp
on the control
panel does not
light.)
●
The l/F cable is
disconnected.
Cause
Checkpoint
Solution
Symptom
The
DC
Check fuse (Fl) on the
Filter unit.
Replace F1.
filter unit is
defective.
line is dead.
Measure the output volt-
age of
filter unit. Re-
fer to Table 2-2.
Measure the resistances
of R21 and
R21:
Replace the
filter unit.
Replace the R21
or
Resistors are
open.
Replace the
Q25, Q24,
or Q23.
Measure the wave-form
of
or Swithcing
transistors. Refer to Fig-
ure 2-9.
Switching regula-
tor
or Switching
transistors are
defective.
Measure the voltage of
Pin 8.
(Pin 8 =
Replace the
or
Fuse
is open.
Check fuse on the
board.
Replace F2.
Replace
or
Measure the waveform of
and
The
DC
line is dead.
Switching regula-
tor
or
switching transis-
tors are defective.
Resistor is open.
Measure the resistance
of
Replace
Reset circuit is
dead.
line is
defective.
Check the
line.
Gate array (36) is
defective.
ROM is
defective.
Gate array is
defective.
Check the level of IC3B
Pin 25.
In operating: High
Replace Gate ar-
ray (3 B).
The printer
mechanism
does not initial-
ize at power on.
Check the pin insertions
of ROM.
Check the level of IC3B
Pin 25.
In operating: High
Replace ROM
[3 C).
Replace Gate ar-
ray
(3 B).
5-12