Epson TM U200D - B/W Dot-matrix Printer Technical Manual page 89

Table 4-2 Troubleshooting table for bad printing
Problem Probable cause
The ribbon in the
ribbon cassette may
be bad.
The printer does
not print. (The
The platen gap may
Motor, carriage
be incorrect.
operates, but
nothing is
The common line of
printed, or the
the Print head unit
print color is
may be bad.
light.)
The FPC, head may
be bad.
The FPC, head may
be bad.
Dots are missing The drive coil of the
continuously. (A Print head unit may be
specific dot is bad.
not printed.)
The dot wires of the
Print head unit may be
bad.
The FPC, head may
be bad.
Dots are missing The Print head unit
occasionally. may be bad.
The Print head unit
may be worn.
Paper particles or
foreign substances
may be attached to
The character
gears or pulley, belt
width is
driving or the belt.
incorrect.
Gears or Pulley, belt
drive or the belt may
be damaged or worn.
The operation of the
paper supply may be
incorrect.
The paper path may
be incorrect.
Paper is not fed.
(Printing is The connector is not
performed on inserted correctly.
one line.)
The Roller, paper feed
may be bad.
The Roller, paper hold
ass'y may be worn or
damaged.
Rev. B
TM-U200D/U200PD Technical Manual
Level Checkpoint
Check if the color of the ribbon
A is faded or the ribbon is
wrinkled or torn.
Check the platen gap.
B
(standard: 0.55 mm ±0.05 mm)
Check the continuity of the
B
common line.
Check the continuity of the
B
common line.
Check the continuity of the F
B
PC, head.
Using the tester, check the
resistance of the corresponding
B
drive coil. (Standard: 19.2 ohm
±5%)
Check if the dot wires are
B
broken.
Check the continuity of the
B
FPC, head.
Check if there are paper
B particles or ink on the tips of the
dot wires of the Print head unit.
The cause is none of the
B
above.
Check if any paper particles or
foreign substances are
B attached to the Pulley, belt
drive, Pulley, belt tension, and
belt.
Check the wear and damage
B of the Pulley, belt drive, Pulley,
belt tension, and belt.
Check if the specified paper
A
roll is used.
Check if the paper supply path
A
is blocked.
Make sure that the pin of the PF
motor cable is inserted in the
A
connector CN6 of the main
circuit board.
Check the wear and damage
B
of the surface of the roller.
Check the wear and damage
B of the rollers of the Roller, paper
hold ass'y.
Action
Replace the ribbon
cassette.
Adjust the platen gap.
(See "Adjustments" in
Chapter 5.)
Replace the Print head
unit.
Replace the FPC, head.
Replace the FPC, head.
Replace the Print head
unit.
Replace the Print head
unit.
Replace the FPC, head.
Remove any paper
particles or ink, or replace
the Print head unit.
Replace the Print head
unit.
Remove any paper
particles or foreign
substances.
Replace any worn or
damaged parts.
Use the correct paper roll.
(See "Paper Specifications"
in Chapter 1.)
Remove paper particles
and foreign substances.
Reinsert the connector.
Replace the Roller, paper
feed.
Replace the Roller, paper
hold ass'y.
Troubleshooting 4-11