Epson Perfection 4870 Photo - Troubleshooting Guide

Perfection 4870 Photo Revision A
TROUBLESHOOTING Troubleshooting 31
3.2 Troubleshooting
This section explains troubleshooting from the superficial phenomena.
In this section, troubleshooting is divided on a unit level, based on the superficial
phenomena at occurrence of trouble. Refer to Table 3-3, find the corresponding
phenomenon, and make checks according to the flowchart.
Table 3-3. Trouble Phenomena, Causes and Reference Flowcharts
Phenomenon Trouble Definition Cause Location
Reference
Flowchart
If powered ON, the
Main Unit does not
operate.
The Main Unit does not
perform initialization
operation.
• Connector
• Power Supply Board
• Carriage Motor
• Main Board
3-1
Occurrence of "Fatal
error".
(The LED flashes red.)
After occurrence of the
above error, recovery
cannot be made if
power is switched on
again.
The Carriage Unit does
not operate.
• Carriage Lock
• Upper Housing
• Connector
•Harness
• Carriage Moving
Mechanism
• CR Motor
• Main Board
3-2
The Fluorescent Lamps
are not lit.
• Connector
• Fluorescent Lamps
• Carriage
• Main Board
3-3
Scanned image quality
error
An image cannot be
scanned clearly.
• Smudge on Document
Glass
• Smudge on Mirror
• Sheet White Section
• CCD Board
• Main Board
3-4
Occurrence of
"Communication
error".
(The LED flashes red.)
After occurrence of the
above error,
"Communication
error" occurs when
communication is
made with the host
again.
The host does not
recognize the scanner if
power is switched on.
• Condition of host
support
(USB, IEEE1394)
•TWAIN Driver
•Cable
(USB, IEEE1394)
• Main Board
3-5
The TPU does not
operate.
The TPU does not
operate.
•Cable
•TPU Main Board
• Main Board
3-6
The TPU Carriage Unit
does not operate.
• TPU Carriage Lock
• TPU Lower Housing
• Connector
•TPU Harness
• TPU Carriage Moving
Mechanism
• TPU CR Motor
•TPU Main Board
3-7
The Fluorescent Lamps of
the TPU do not light up.
• Connector
• Fluorescent Lamps
• TPU Carriage
•TPU Main Board
3-8
The LED of the TPU does
not light up.
• Connector
• Sub_C Board
Sub_D Board
• TPU Carriage
•TPU Main Board
3-9
Table 3-3. Trouble Phenomena, Causes and Reference Flowcharts
Phenomenon Trouble Definition Cause Location
Reference
Flowchart