NEC MultiSync LCD1920NX User And Service Manual page 81

TROUBLE SHOOTING
TABLE OF CONTENTS
1. Power is not available .......................................................................................................... 6-2
2. No image display ................................................................................................................. 6-3
2.1 LED light, but no OSD, no back light and no image .......................................................... 6-3
2.2 LED green, and no OSD and no back light ........................................................................ 6-4
2.3 LED green, and OSD present, but no image ..................................................................... 6-5
3. Picture errors ....................................................................................................................... 6-6
3.1 High-light in white or black
3.2 Image is unclear ................................................................................................................. 6-7
3.3 Image noise ....................................................................................................................... 6-8
4. Others operational error ....................................................................................................... 6-9
4.1 DDC read error .................................................................................................................. 6-9
4.2 Back light malfunction ........................................................................................................ 6-9
5. Switching power circuit failure ........................................................................................... 6-10
Note
Prior to the diagnostic servicing for troubleshooting, the following items should be examined to
confirm the freedom from abnormality:
(1) Power supply voltage: 100 to 240VAC
(2) Input signal: 1280 x 1024 (60Hz), recommended (Separate)
A: Analog D-SUB input
Display pattern
(3) All connectors shall be correctly connected in the unit.
< Explanations below are based on the analog D-SUB input.>
............................................................................................... 6-6
RGB 0.7Vp-p (when terminated with 75Ω)
Display not in black
6-1
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