Repairing The Printer Mechanism - Epson LQ-2170 Service Manual

LQ-2170 Service Manual

5.6 REPAIRING THE PRINTER MECHANISM

This section provides instructions for repairing the printer mechanism. It describes various problems,
symptom, likely causes, checkpoints, and solutions. The checkpoint column shows items to be checked,
including proper values to be set for each component of the printer mechanism. For replacement and
adjustment instructions, see Chapter 3, Disassembly and Assembly, and Chapter 4, Adjustments. If the same
symptom recurs after repair, select another item in the list of causes and repair the printer according to those
instructions.
Table 5-8. Repairing the Printer Mechanism
Problem
When the printer is
CR operation is
abnormal.
CR motor does not
When the printer
is powered on,
the CR motor
^
does not rotate all
and all indicators
blink.
The CR motor
can be rotated
when the printer
^
is powered on.
But the CR does
not move.
The CR moves
slightly and then
stops.
^
^
^
Rev.A
Symptom
The CR motor is
defective.
powered on, the
rotate at all.
CN11 is
disconnected
from the main
board.
The timing belt
came off the
pinon gear of
the CR motor.
Platen gap is
too narrow.
Printer lacks
lubrication or a
foreign object is
jammed
between the oil
pad and CR
shaft.
HP sensor is
defective.
Cause Checkpoint
Measure the
coil resistance
of the motor.
Resistance is
approximately
2.7 ohms.
Check CN11.
Check the
engagement of
the timing belt.
Manually move
the CR and
check that it
moves
smoothly. The
proper platen
gap is
approximately
0.37 mm.
Manually move
the CR and
check that it
moves
smoothly.
Check the
surface of the
CR shaft and oil
pad.
Check the
operation of the
HP sensor.
Refer to page
5-2.
Troubleshooting
Solution
Replace the CR
motor. Refer to
page 3-12.
Connect CN11
correctly.
Reinstall the
timing belt
correctly.
Adjust the
platen gap
properly.
Refer to page
4-2.
Replace or
lubricate the oil
pad. If any
foreign object is
jamming the
carriage,
remove it and
clean the
surface of the
CR shaft. Then
lubricate the CR
shaft.
Replace the HP
sensor. Refer
the page 3-8.
5-15