Service manual

Rev. 2.00
- 125 -
SRP-275
7-2-2 Printing quality problems
Problem Probable Cause Level Checkpoint Action
FPC-head connector is disconnected
with PCB-head ass’y and Printer-
head
B
Check if the FPC-head is
properly inserted into its
connector of head and its
board
If is not, securely
reinsert the FPC-
head
Broken common lead of FPC-head
B
Check the conductivity
between the common lead of
FPC-head and other
terminals
Replace the HEAD
unit, if there is no
conductivity
FPC(30pin) between the PCB-head
ass’y and PCB-main ass’y is broken
B
Check the conductivity of the
FPC(30pin)
Replace the FPC
(30pin) if there is no
conductivity
Positional relationship between
Printer-head and Platen
B
Check if the gap between the
platen and the pin of head is
correct value : 0.40±0.05mm
Correct the gap
Ribbon cassette is absent
A
Check Ribbon cassette’s
existence
Insert
Ribbon cassette
HF motor
rotates
normally but
no dot printing
is performed
Input pulse irregularity B
Check firing input pulse with
an oscilloscope
Replace
PCB-main ass’y
Damaged lead in FPC-head
B
Check the conductivity of
lead of FPC-head
Replace FPC-head
Positional relationship between the
head and the platen
B
Check if the gap between the
platen and the pin of head is
correct value : 0.40±0.05mm
If incorrect,
performed repair with
reference
FPC(30pin) is failure or disconnected
between PCB-head ass’y and PCB-
main ass’y
B
Check the connected
condition of FPC and FPC
failure
Make sure the
connection and
replace the FPC
A certain dot
does not print
Defective Printer-head
B
Check head response to
command with oscilloscope
Replace
Printer-head
Belt tension is loose B
Check Spring-lever-tension
for deformation
Replace or
reassemble Spring-
lever-tension
Carriage drive area contamination B
Check gears and pulleys for
dirt deposits or other foreign
matter
Remove any dirt
deposits or foreign
matter
Character
width changes
irregularly
Carriage drive parts wear or damage B
Check if there are defective
parts among gears
Replace defective
gear
Ribbon cassette is exhausted
A
Check for ink of ribbon
cassette
Replace
Ribbon cassette
Head gap is not correct between
head and platen
B Check the gap
If incorrect, performed
repair with reference
Print is very
faint
Defective Printer-head
B
Check head response to
command with oscilloscope
Replace
Printer-head