Epson Perfection 640U Series, Руководство по обслуживанию

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EPSON Perfection 640U Revision A
Troubleshooting Troubleshooting 21
3.3 Troubleshooting
This section describes how to troubleshoot problems according to
exhibited phenomenons.
See Table 3-2 that enables you to find the defective part to the unit
level. Then refer to the corresponding table for checkpoints and
solutions.
Table 3-2. Problems and Corresponding Tables to Refer to
Phenomenon Problem Refer to:
The scanner is turned on but
does not operate. The scanner is not initialized. Table 3-3
“Fatal Error” occurs. The
scanner is turned off and back
on but still shows the same
error. The carriage unit does not
operate. Table 3-4
The carriage unit operates but
the error is indicated. Table 3-5
The lamp does not light up. Table 3-6
Image is not read clearly. Image is not read clearly. Table 3-7
“Communication Error” occurs.
Communication with the host
is attempted again, but the
same error occurs. USB interface error Table 3-8
Table 3-3. The scanner is not Initialized.
Cause Step Checkpoints Finding Remedy
Connector is
disconnected.
1
Check all connectors.
Are any connectors
disconnected?
Yes
Connect any
disconnected
connectors.
No
Replace the main
board.
Table 3-4. The carriage unit does not operate.
Cause Step Checkpoints Finding Remedy
CN3 on the
main board is
disconnected. 1 Check that CN3 is disconnected. Yes Connect CN3 on
the main board
properly.
The carriage
drive
mechanism is
defective.
2
Is grease (G-26) properly
applied?
(See Chapter 6.) No Apply grease to
the specified
points properly.
3 • With the upper housing
removed, turn the scanner on,
and check that the CR motor is
live.
• Remove the CR motor, and
check that the carriage unit
moves smoothly.
No Check the
carriage unit,
and replace any
defective part or
disassemble and
assemble the
scanner again.
The CR motor
is defective. 4 Disconnect CN3 on the main
board. Then, using a tester,
check that the coil resistance at
each point below is 4.8
Ω .
1. Between Pins 2 and 4 (Motor
side)
2. Between Pins 1 and 3 (Motor
side)
No Replace the CR
motor.
The main
board is
defective. 5 --- --- Replace the
main board.
Table 3-5. The carriage unit operates but the error is indicated.
Cause Step Checkpoints Finding Remedy
The scanner
upper case has
been removed.
1 Has the scanner upper
case been removed? Yes
Install the
scanner upper
case.
Problem with
main circuit
board
2 --- ---
Replace the main
circuit board.