
L7C SERIES LCD Monitor Service Manual (v1.0)
TABLE OF CONTENTS
1. Precaution and Notices … … … … . … … … … … … … … … … … … … … … 3
1.1 Safety Precaution … … … … . … … … … … … … … … … … … … … … . 3
1.2 Product Safety Notice … … … … … … … … … … … … … … … … … … 3
1.3 Service Notes … … … … … … … … … … … … … … … … … … … … … . 3
2. Specifications … … … … . … … … … … … … … … … … ... … … … … … … … 4
2.1 Monitor Specifications … … .. … … … … … … … … … … … … … … … . 4
2.2 Timing Supported – Analog Inputs .. … … … … … … … … … … … … . 5
3. Control Buttons and Functions … … … … … … … … … … … … … … … … . 6
4. Disassembly Instructions … … … … … … … … … … … … … … … … … … .. 6
5. General Connection and Applications … … … … … … … … … … … … … .. 6
5.1 Connecting the Monitor to the Computer … … … … … … … … … … .. 9
6. Electronic Block Diagram … … … … … … … … … … … … … … … … ..... 11
Appendix A. Troubleshooting Flow Chart
Appendix B. Mainboard Circuit Diagrams
Appendix C. Keyboard Circuit Diagrams
Appendix D. Audio Circuit Diagrams
Appendix E. Mechanical Disassembly
Appendix F. Service Parts List

L7C SERIES LCD Monitor Service Manual (v1.0)
1. Precautions and Notices
1.1 Safety Precautions
Although LCD monitors are displays without high voltage as that in the CRTs, the
following precautions still should be take care of.
1) Observe all cautions and safety related notes located inside the display cabinet and on
the display chassis.
2) Operation of these displays outside the cabinet or with the cover removed involves a
shock hazard from the display backlight’s inverter. Work on the display should not be
attempted by anyone who is not thoroughly familiar with precautions necessary when
working on high voltage equipment.
3) Before returning a serviced display to the customer, a thorough safety test must be
performed to verify that the display is safe to operate without danger or shock.
1.2 Product Safety Notice
1) Many electrical and mechanical parts in this chassis provide special visual safety
protection. The protection afforded by them cannot necessarily be obtained by using
replacement components rated for higher voltage, wattage, etc.
2) Before replacing any of these components, read the parts list manual carefully. The use
of substitute replacement parts, which do not have the same safety characteristics, as
specified in the parts list may create shock, fire or other hazards.
1.3 Service Notes
1) When replacing parts or circuit boards, wrap the wires around terminals before
soldering.
2) Keep wires away from high temperature components.
3) Keep cable and their shielding in their original position so as to reduce interference.

L7C SERIES LCD Monitor Service Manual (v1.0)
2. Specifications
2.1 Monitor Specification
LCD Module 17-in, active matrix TFT, anti-glare coating, 0.264 mm pixel pitch
Display Size 337.9 mm x 270.3 mm
Viewing Angle
Left/Right
Up/Down
80° / 80°(Typical)
40° /80°(Typical)
Luminance
Contrast Ratio
250 cd/m2 (Typical)
400 : 1 (Typical)
Display Colors 16.7 million
Power Input 100 ~ 240 VAC Full Range, 50/60 Hz (External AC adapter)
Maximum power
consumption
< 45W
Signal Input
Video Signal
Sync signals
RGB positive 0.7VPP, 75ohm
Separate & Composite, TTL Level
Line (horizontal)
frequency
31.5 kHz ~ 80 kHz
Raster (vertical)
frequency
56 Hz ~ 75 Hz
Pixel dot clock 135 MHz (maximum)
Recommended mode 1280 x 1024 @ 60 Hz
Pedestal tilt
20° forward, -5°backward
Dimensions
(W x H x D)
424 x 438 x 86 mm (without base)
Weight 7.0 kg
Operating Conditions
Temperature
Humidity
Altitude
5° ~ 40°C at altitude 0 ~ 2000m
5° ~ 30°C at altitude 2000 ~ 3000m
20% ~ 85% RH, non-condensing
3000m Max.
Storage Conditions
Temperature
Humidity
Altitude
-20° ~ 60°C
5% ~ 95% RH
10000m Max.

L7C SERIES LCD Monitor Service Manual (v1.0)
2.2 – Analog Inputs
Mode
No.
Mode Name
Resolution
1 VGA 60HZ
640*480
2 VGA 72HZ
640*480
3 VGA 75HZ
640*480
4 SVGA 56HZ
800*600
5 SVGA 60HZ
800*600
6 SVGA 72HZ
800*600
7 SVGA 75HZ
800*600
8 XGA 60HZ
1024*768
9 XGA 70HZ
1024*768
10 XGA 75HZ
1024*768
H.Freq.(KHZ)
V.Freq.(HZ)
31.469
59.941
37.804
72.81
37.5
75.0
35.156
56.25
37.879
60.317
48.077
72.188
46.875
75.0
48.363
60.004
56.476
70.069
60.023
75.029
H. Polarity
V. Polarity
-
-
-
-
-
-
+
+
+
+
+
+
+
+
-
-
-
-
+
+
Pixel CLK
(MHZ)
25.175
31.5
31.5
36.0
40.0
50.0
49.5
65.0
75.0
78.75
11 SXGA 60HZ
1280*1024
12 SXGA 75HZ
1280*1024
13 MAC SVGA
640*480
14 MAC SVGA
832*624
15 US TEXT
720*400
16 VGA 70HZ
640*350
63.981
60.020
79.976
75.025
35.0
66.667
493725
74.550
31.469
70.087
31.469
70.087
+
+
+
+
-
-
-
-
-
+
+
-
Note: The display is capable of going beyond these recommended modes.
108
135
30.24
57.283
28.322
25.175

L7C SERIES LCD Monitor Service Manual (v1.0)
3. Control Buttons and Functions
There are four control buttons located at the lower part of the front panel of your display:
ð POWER: Push to turn on or turn off the display. The power indicator (Green) will light
while the display is on.
ð Select: Display the On-Screen Display (OSD) “Main Menu” , selects items for user
adjustment, and execute the function selected.
Note: Hold down this key for 2 seconds will clear OSD menu.
ð Up(△): Move upward through the choice in the OSD submenu. If an adjustment bar is
displayed, this button increases the setting value.
Note: This key is also used as ‘direct key’ to bring-up OSD “Audio Menu”.
ð Down(▽): Move downward through the choice in the OSD submenu. If an adjustment bar
is displayed, this button decreases the setting value.
Note: This key is also used as ‘direct key’. When the OSD “Main Menu” is inactive, press
this key will execute ‘Auto Setup’ function.
Detail contral function please reference User’s Manual
4. Disassembly Instructions
To disassembly the monitor, follow the steps as below:
1) Face Down the Monitor.
Note: Face down the monitor on a smooth plane with a soft material on that plane to
protect the panel faceplate.
2) Hinge Cover Removal
As below, remove the screw indicated by “A” from the hinge cover, and then remove the
hinge cover (indicated by “B”) for the base.

L7C SERIES LCD Monitor Service Manual (v1.0)
3) Base and Back Cover Removal:
As below, after removing the hinge cover, there will be 4 screws (indicated by “C”), and
remove them. Then you can remove the whole base of the monitor.
Remove 4 screws indicated as “D” of the back cover. Then remove the back cover with
care .