ViewSonic Va703b3 Service Manual
Here you can view all the pages of manual ViewSonic Va703b3 Service Manual. The ViewSonic manuals for Display are available online for free. You can easily download all the documents as PDF.
Page 41
2. No Power & Power LED Off
No power
Check primary
rectifier voltage Check IC802,
C805, T801 Check circuit
if short
Check F801, P801,
D801...
Page 42
3. DC output voltage is unstable Output Voltage Unstable Check Vbe of Q801 below 0.3V Check circuit if short Check ZD801, D803, D805 Check Q802 Check reference voltage Check pinR of IC801 Check R809, R814, IC801, R818 Check R810, R811 Check feedback circuit Check Vpin3-4 of IC801 about 6V Check Vpin1-2 of IC801about1V Check C815, D806, R812 Check R809, R814 END 39 ViewSonic Corporation Confidential - Do Not Copy VA703b-3_VA703m-3
Page 43
4. Output power is unstable
Unstable power
Check sampling
Circuit Check R810,
R811, R818
Change R810, R811,
R818
Check the R pin
voltage of IC803
about 2.5V
Check R809, R808, R814,
D809
Check D806, C815 if
short
Change
D806, C815
Check pin1 of
IC802 voltage
is 5.8V
Check pin3 of
IC802 voltage
about 1V Change R801, R805, R822, R823, R817...
Page 44
5. Backlight can’t be turned on No raster? LED Green? Ye s Ye s Ye s Backlight can’t be turned on. No Check power supply Is there high-level voltage on pin10 of IC501? No Is Ok R526? Check I/F board Ye s R526 open No Ye s Is there instantaneously pulse wave on pin1, pin3, pin15 of IC501 at the moment of restart? No Is Ok...
Page 45
6. Black Screeqn and backlight turn on Black Screen Power FailCheck Power Supply: Pin 1, 2 of CN101 Check Power: Pin 2 of U101 and Pin 2 of U102 Check Reset Waveform(Pin 84 of U105) Check Crystal Waveform(Pin 96,97 of U105) U101, U102 Fail Check X101,C153, C154 U105 (TSUM16AL) Fail NG OK NG OK NG OK OK NG Check C144 and R172 42 ViewSonic Corporation Confidential - Do Not Copy VA703b-3_VA703m-3
Page 46
7. White Screen W hite Screen W orkm anshipLVD S Cable R einsert Change LVD S C able Check VLCD is 5V? C heck Panel-Enable of U 105(pin48) is high? LVD S C able N G U105 Fail U105 Fail END OK NG OK NG OK OK NG OK NG NG C heck LVD S signalsP a n e l F a il Check Q 101, Q 103, Q 107, R 105, R 106, C108, C 109, C111 C heck V cc5V ?Power Fail OK OK NG 43 ViewSonic Corporation Confidential - Do Not Copy VA703b-3_VA703m-3
Page 47
8. Bad Screen Bad Screen Workmanship LVD S C able N G Check X101, C 153, C154 C heck Pin 37, 38, 39, 40 of U 105 END LVDS C able R einsert Change LVD S C able C heck C rystal:pin96, 97 of U105 C heck the com m unication ofU 105 and U 106 OK NG OK NG NG OK NG OK C heck the pins of C N 104U105 FailNG 44 ViewSonic Corporation Confidential - Do Not Copy VA703b-3_VA703m-3
Page 48
45 ViewSonic Corporation Confidential - Do Not Copy VA703b-3_VA703m-3 7. Recommended Spare Parts List Rev: 1c Serial No. Prefi xQAG Item DescriptionECR/ECN ViewSonic P/N Ref. P/N Location Universal number# 1 Power Cord 10A/250V Australia A-00003671 453070800420R 2 Power Cord UK3Gx.75mm Singapore A-00003675 453070800230R 3 Power Cord 10A/250V(china) A-00005255 453070800170R 4 Power Cord 10A/125V A-00006679 453070800250R 5 Kit, Accessory A-00006730 703000002310R 6 Kit, Accessory CPT,...
Page 49
46 ViewSonic Corporation Confidential - Do Not Copy VA703b-3_VA703m-3 Rev: 1c Serial No. Prefix: QAF Item ECR/ECN ViewSonic P/NRef. P/N Location Universal number#1Power Cord 10A/250V Australia A-00003671 453070800420R 2 Power Cord 16A/250V A-00003674 453070800210R 3 Power Cord UK3Gx.75mm Singapor eA-00003675 453070800230R 4 Power Cord (CHINA)A-00005255 453070800170R 5 Power Cord, VCTF 3Gx0.75 A-00006733 453070800480R 6 Power Cord 1,H05VV-F 3Gx Kore aA-00006734 453070800500R...
Page 50
ViewSonic Model Number: VS11359 Rev: 1c Serial No. Prefix: QAG Item ViewSonic P/N Ref. P/N Description Location Universal number# Qty1N/A506380001800R TAPE,WRAPPING TYPE,48mmx50M ROHS LE1915 For World Wide1.200 2N/A506380002100R TAPE,WRAPPING TYPE(VIEWSONIC),50mmx75M,LFor World Wide0.513 3N/A506431000300R FILM,PE 500mmx900M ROHSFor World Wide0.050 4 P-00006718 506040008800R CUSHION,EPS-L, LE1734For World Wide100.000 5 P-00006719 506040008810R CUSHION,EPS-R, LE1734For World Wide100.000 6N/A506150006000R...