Epson V500, Service Manual

Page: 25 / 69

EPSON Perfection V500 Photo Revision A
TROUBLESHOOTING Overview 25
3.1 Overview
This chapter explains the remedies for errors detected by the scanner’s self-diagnostic
function, and provides a troubleshooting guide based on observed problems.
3.1.1 Self-Diagnosing
This scanner has a self-diagnostic function that automatically diagnoses the operating
status of major components, and uses an LED indication to show the error status. This
function detects the following error statuses shown in the table below. The corrective
action is also listed.
COMMAND ERROR
FATAL ERROR
3.2 Troubleshooting
This section provides troubleshooting procedures based on observed faults. Refer to
Table 3-3 , and choose the table describes the general fault indication. Within the table,
find the Problem that most closely matches what you observe and follow the
procedures given in the table cross referenced in the right-hand column.
Table 3-1. Command Error
LED Indication Cause Disposition
• Unidentified command is
detected.
• The scanner (interpreter)
ignores the incorrect command
or parameter. The current
settings are maintained.
• Scanner (interpreter) returns
NACK, and waits for the next
command or parameter.
Recovery The error condition is canceled upon receipt of a valid command.
Table 3-2. Fatal error
LED Indication Cause Disposition
• The main unit is faulty.
(the carriage does not return to
the home position or any other
mechanical error)
• Firmware downloading failed.
• The Scanner turns the carriage
lamp off and stops the operation.
• The Scanner sets Bit 7 of the
status bit.
Recovery Turn the scanner off and then back on.
(None)
(Rapid flashing,
orange)
Table 3-3. Trouble Phenomenon, Cause and Troubleshooting Table
Problem Definition
Troubleshooting
Table
Scanned image quality error. Scanned image is not clear.
3-4
The main unit does not operate
when powered-on. The Main Unit does not perform
initialization operation.
3-5
The host does not recognize the
scanner when power is switched on.
3-6
Fatal error.
(The LED flashes orange.)
The scanner does not recover from
the error even after power-off and
back on.
The Carriage Unit does not operate.
3-7
The LED does not light (main unit)
3-8
The TPU does not work at all. The TPU does not operate.
3-9
The TPU Carriage Unit does not
operate.
3-10
The LED does not light (TPU unit)
3-11
Table 3-4. Scanned Image Quality Error.
Step Possible Cause Corrective Action
1
The Document Glass is not clean. (Image
has white spots) Clean the glass.
(Refer to
6.1.1 Cleaning
)
2
The mirror in the Carriage is not clean.
(Vertical bands appear on the image.) Clean the mirror.
(Refer to
6.1.1 Cleaning
)
3
Upper Housing failure
(The white document mat is deformed or is
not clean.)
Replace the Upper Housing.
4 CCD Sensor Board failure Replace the Carriage Unit.
5 Main Board failure Replace the Main Board
6 Carriage mechanism failure Replace the Carriage mechanism.