Troubleshooting - Epson 1240U Service Manual

EPSON Perfection 1240U

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
The scanner is turned on but The scanner is not initialized.
does not operate.
"Fatal Error" occurs. The The carriage unit does not
scanner is turned off and back operate.
on but still shows the same
The carriage unit operates but
error.
the error is indicated.
The lamp does not light up.
Image is not read clearly. Image is not read clearly.
"Communication Error" occurs. USB interface error
Communication with the host
is attempted again, but the
same error occurs.
Table 3-3. The scanner is not Initialized.
Cause Step Checkpoints
Connector is Check all connectors.
1
disconnected. Are any connectors
disconnected?
Troubleshooting
Problem Refer to:
Table 3-3
Table 3-4
Table 3-5
Table 3-6
Table 3-7
Table 3-8
Finding Remedy
Connect any
Yes disconnected
connectors.
Replace the main
No
board.
Troubleshooting
Table 3-4. The carriage unit does not operate.
Cause Step Checkpoints
CN3 on the 1 Check that CN3 is disconnected.
main board is
disconnected.
The carriage Is grease (G-26) properly
drive applied?
2
mechanism is
(See Chapter 6.)
defective.
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.
The CR motor 4 Disconnect CN3 on the main
is defective. board. Then, using a tester,
check that the coil resistance at
each point below is 4.8
1. Between Pins 2 and 4 (Motor
side)
2. Between Pins 1 and 3 (Motor
side)
The main 5 ---
board is
defective.
Table 3-5. The carriage unit operates but the error is indicated.
Cause Step Checkpoints
The scanner
1 Has the scanner upper
upper case has
case been removed?
been removed.
Problem with
2 ---
main circuit
board
Revision A
Finding Remedy
Yes Connect CN3 on
the main board
properly.
No Apply grease to
the specified
points properly.
No Check the
carriage unit,
and replace any
defective part or
disassemble and
assemble the
scanner again.
No Replace the CR
motor.
Ω
.
--- Replace the
main board.
Finding Remedy
Install the
Yes
scanner upper
case.
Replace the main
---
circuit board.
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