Keypad Operation Impossible; Lcd/Led Malfunction - Epson EPL-N3000 Service Manual

EPSON EPL-N3000/AcuLaser M4000N

3.3.2 LCD/LED Malfunction

Table 3-54. Troubleshooting for LCD/LED Malfunction
Step Action and Question
Parts below can be the source of this error
• CONTROL PANEL
(p.170)
• WIRE HARNESS
• HVPS/MCU
(p.301)
• LVPS
(p.287)
3.3 VDC Power Supply
1. Check the voltage across the harness of the
1
OPERATION PANEL.
♦
Is the voltage 3.3 VDC across the harness of the
OPERATION PANEL?
OPERATION PANEL (1)
2 1. Check continuity of each wire of the WIRE
HARNESS.
♦
Does each wire of harness have continuity?
OPERATION PANEL (2)
3
1. Replace the OPERATION PANEL.
♦
Has the display been stabilized?
OPERATION PANEL (3)
4
♦
Is the voltage between P/J28-5↔P/J28-4 on the
BOARD ASSY., MAIN 3.3 VDC?
FCC ASSY ESS
1. Disconnect P/J28 of the HVPS/MCU.
5 2. Check continuity between the following connectors.
P/J28-5↔P/J280-22
P/J28-4↔P/J280-23
♦
Is there normal continuity in each wiring?
Troubleshooting
Yes No
(Chapter 4 Disassembly and
Assembly)
Go to Step 2 Go to Step 4
Replace the
HARNESS
Go to Step 3
ASSY
PANEL
Replace the
Problem BOARD
(p.170)
solved ASSY.,
MAIN
Replace the
BOARD
Go to Step 5
ASSY.,
MAIN
Replace the
Replace the
BOARD
FCC ASSY
ASSY.,
ESS
MAIN
Troubleshooting for Faulty Operation

3.3.3 Keypad Operation Impossible

Table 3-55. Troubleshooting for Keypad Operation Impossible
Step Action and Question
Parts below can be the source of this error
• CONTROL PANEL
(p.170)
• HARNESS ASSY PANEL
• HVPS/MCU
(p.301)
• LVPS
(p.287)
3.3 VDC Power Supply
1. Check the voltage across the harness of the
1
OPERATION PANEL.
♦
Is the voltage 3.3 VDC across the harness of the
OPERATION PANEL?
OPERATION PANEL (1)
2
1. Check continuity of each wire of harness.
♦
Does each wire of harness have continuity?
OPERATION PANEL (2)
3
1. Replace the OPERATION PANEL.
♦
Has the display been stabilized?
OPERATION PANEL (3)
4
♦
Is the voltage between P/J28-5↔P/J28-4 on the
BOARD ASSY., MAIN 3.3 VDC?
FCC ASSY ESS
1. Disconnect P/J28 of the HVPS/MCU.
2. Check continuity between the following connectors.
5
P/J28-5↔P/J280-22
P/J28-4↔P/J280-23
♦
Is there normal continuity in each wiring?
Revision C
Yes No
(Chapter 4 Disassembly and
Assembly)
Go to Step 2 Go to Step 4
Replace the
HARNESS
Go to Step 3
ASSY
PANEL
Replace the
Problem BOARD
(p.170)
solved ASSY.,
MAIN
Replace the
BOARD
Go to Step 5
ASSY.,
MAIN
Replace the
Replace the
BOARD
FCC ASSY
ASSY.,
ESS
MAIN.
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