SERVICE MANUAL
17
"
LCD Monitor
786LS
All manuals and user guides at all-guides.com
all-guides.com
Page 1: ...SERVICE MANUAL 17 LCD Monitor 786LS All manuals and user guides at all guides com a l l g u i d e s c o m...
Page 2: ...BEEN MADE TO ENSURE THE ACCURACY OF THIS MANUAL WE CANNOT GUARANTEE THE ACCURACY OF THIS INFORMATION AFTER THE DATE OF PUBLICATION AND DISCLAIMS RE LIABILITY FOR CHANGES ERRORS OR OMISSIONS MANUFACTU...
Page 3: ...NS 7 4 2 ADJUSTMENTS METHOD DESCRIPTION 7 8 4 3 FRONT PANEL CONTROL KNOBS 9 5 CIRCUIT SOFTWARE DESCRIPTION 10 5 1 SPECIAL FUNCTION WITH PRESS KEY 10 5 2 CIRCUIT FUNCTION DESCRIPTION 10 11 5 3 SOFTWARE...
Page 4: ...ncies Horizontal 30 KHz 83 KHz Vertical 55 Hz 75 Hz Pixel clock 135 MHz 6 Factory Preset Timing 17 User Timings 13 Input signal tolerance H tolerance 1 K V tolerance 0 5 Hz 7 Input Power Source Switch...
Page 5: ...l The Adapter will provides the 12V DC power 4 16 Amp to Main board and Inverter module Monitor Block Diagram 1 2 Interface Connectors A AC Power Cable B Video Signal Connectors and Cable C External A...
Page 6: ...change variable resistance settings in MAIN BOARD they are adjusted to the most suitable value If they are changed it might happen LUMINANCE does not satisfy the white balance spec 3 Please consider t...
Page 7: ...e connector information is as follow 15 Pin Color Display Signal Cable PIN NO DESCRIPTION PIN NO DESCRIPTION 1 RED 9 5V power from VGA card 2 GREEN 10 GND 3 BLUE 11 SYNC GND 4 GND 12 SDA 5 GND 13 HORI...
Page 8: ...to 7200 color and MEM channel 2 to 6500 color our 7200 parameter is x 302 20 y 319 20 Y 200 20cd m2 and 6500 parameter is x 313 20 y 329 20 Y 200 20 cd m2 How to setting MEM channel you can reference...
Page 9: ...ve the adjustment result b adjust 6500 color temperature 1 Set the Contrast of OSD function to 45 and Adjust Brightness to chroma 7120 Y 240 5 cd m2 2 Switch the chroma 7120 to RGB mode with press MOD...
Page 10: ...he Chroma to pattern 1 crosshatch pattern or WIN98 95 full white pattern confirm above item 2 3 functions clock focus was done well if that 2 functions failed the H V position will be failed too Adjus...
Page 11: ...gital data with interpolation process zooming generated the OSD font perform overlay function and generate drive timing for LCD PANEL 2 U302 89C51RD2 PHILIPS MCU type 8052 series with 64k Rom size and...
Page 12: ...MZAN2 U200 LVDS chip U601 U602 Panel Power Control U202 MCU U302 Data Digital RGB Panel Control Signal Phs Pvs PclkA B Pdispe Panel Power 5V Communication signal Hclk Hfs Hdata0 Input analog RGB H V d...
Page 13: ...lue Initial GMZAN2 Yes POWER ON START Initial MCU I O Interrupt vector Ram Initial 1 POC backlight counter 2 Clr all mode value Yes Check if in Factory mode when power on press the MENU Button will be...
Page 14: ...t support be confirm Set mode index parameter Set change mode flag No No Yes Yes confirm the frequency Hsyn or Vsyn from IFM already been changed check the change mode flag Process turn off OSD settin...
Page 15: ...t Block Check U200 Data output Block OK Panel Power OK Replace Inverter and Check Inverter control relative circuit Re do White balance adjust OK U200 data OK Check Power switch is in Power on status...
Page 16: ...relative circuit R315 Q304 R311 In normal operation when LED green R315 Bklt On should 0 v If Bklt On no response when the power switch turn on off Replace the MCU NG OK Re do white balance OK Measur...
Page 17: ...nough Yes Voltage normal Check the LVDS Power L601 L602 L603 L604 L900 3 3V Check the both U601 U602 LVDS Input pin 31 45mhz 65mhz and pin 27 Vsyn freq pin 28 45khz 65 khz Yes Voltage normal Yes Frequ...
Page 18: ...and crystal OK Check U302 MCU pin 43 42 41 40 39 at High state 5V without press any key Mechanical was stuck Check NG NG If still no Led green indicator check Q102 R106 LED at keyboard cold solder or...
Page 19: ...U200 Gmzan2 was shut down and only U302 MCU still working that means the monitor is in power saving status all power system is working well OK Check U304 pin 2 is a stable rectangle wave Around 150k...
Page 20: ...your noise only exist in one mode only ex only at 1280x1024 75 Hz other is normal OK OK Yes has extension NG interferences still exist NG NO additional extension cable That was cause by you VGA CARD...
Page 21: ...ightness maximal RGB 50 Quit from OSD screen measured Y luminance With chroma 7120 check Y 240 10 cd m2 NG If the Y less than 200 cd m2 after the contrast brightness max then change the LAMP of panel...
Page 22: ...NO SM02B BHSS 1 TB PIN SYMBOL DESCRIPTION 1 HV OUTPUT Input H V to lamps 2 RETURN Return to control C FUNCTION SPECIFICATIONS The data test with the set of SAMPO DC TO DC CONVERTER ROOM TEMPERATURE 2...
Page 23: ...22 D FUNCTION TEST CIRCUIT CON1 1 2 3 4 5 120K 120K 120K 120K 10 10 10 10 VT 181 1 2 1 2 VT 181 VT VT 1 2 1 2 CON2 CON3 CON4 CON5 All manuals and user guides at all guides com...
Page 24: ...D F1 4 0A 63V TO CHECKED Q4 Q6 VOUT 9V TO CHECKED L1 L2 INPUT 9V TO L1 OR L2 TO CHANGED CH1 Q4 Q3 Q11 CH2 Q5 Q6 Q12 TO CHANGED CH1 Q7 Q8 D12 PT1 CH2 Q9 Q10 C13 PT2 FUNCTION TEST OK 1 SHORT R30 OPEN LO...
Page 25: ...IP THE OSCILLATOR FREQUNCY RANGE 150 250 KHZ TO CHANGE C6 CHIP OR IC CHIP FUNCTION TEST OK IF ENABLE ABNORMALITY 1 TO CHECK IC PIN 9 TURN ON HAVE 12 VOLTAGES TO CHANGE ON Q1 Q2 FUNCTION TEST OK IF DIM...
Page 26: ...2 AC VTVM VT 181E 3 DIGITAL MULTIMERTER MODEL 34401 4 HIGHTVOLT PROB MODEL 1137A 5 SCOPE MODEL V 6545 IF TRANSFORMER ABNORMELITY TO CHECK C3 C4 CHIP OUTLINE OR TRANSFORMER TO CHANGE C3 C4 OR TRANSFORM...
Page 27: ...26 7 MECHANICAL OF CABINET FRONT DIS ASSEMBLY All manuals and user guides at all guides com...
Page 28: ...1TKK426C Stand 705L782KB34008 Stand Assy 1 34L919 AM B Stand 1 15L5711 1 Plate 1 Q1L1030 10 47 Screw 2 12L381 1 Foot Pad 4 37L448 1 Hinge 1 33L4345 AM L Dust Cover PE 1 34L918 AM B Dust Cover Stand Ba...
Page 29: ...3911TKK425J CN603 33L801724A H Connector Panel 1 17 3911TKK425K CN302 33L3802 9H Connector Key 1 18 3911TKK425L Cn303 33L3802 5H Connector Inverter 1 Screw Assy M1L330 6 128 Screw 10 M1L1030 10 128 S...
Page 30: ...system LM2596S 5 12V to 5V 5A SPEC 5V To CPU Eeprom 24c21 control inverter on off 860mA when Cable not Connected 841mA when Normal operation To Hyundai 300 Panel around 1450mA AIC1084 5V to 3 3V 5A SP...
Page 31: ...connector Inverter connector MCU Panel Power Control AIC1084 5V to 3 3v LVDS power LT1117 5V to 3 3v LM2596 convert 12V to 5V Input Connector DDC chip RT9164 5V to 2 5v Audio connector All manuals and...
Page 32: ...2002 Title Size Document Number Rev Date Sheet of RT9164 2 5V CRYSTAL2 50MHZ OUT VCC 2 5V 3 3V LM2596 5 0V 5 0V 12V 5V 5V 5V 3 3V ZAN2 SCALER TCLK1 3 3V MFB2 MFB7 MFB8 MFB9 HCLK HFS IRQ HDATA0 RST RST...
Page 33: ...A ADC_GND2 ADC_GND1 SUB_GNDA ADC_GNDA ADC_BGNDA ADC_GGNDA ADC_RGNDA OSD_DATA3 OSD_DATA2 OSD_DATA1 OSD_DATA0 OSD_CLK OSD_VREF OSD_HREF OSD_FSW PD47 PD46 PD45 PD44 PD43 PD42 PD41 PD40 PD39 PD38 PD37 PD3...
Page 34: ...TXO6 TXE5 PCLKB PD40 GND GND PD34 PD23 PD47 TXE0 TXO4 GND TX3 E PD4 TXO10 GND PD3 TXE9 TX2 E PD27 C605 10uF 16V EVEN TX0 E PD33 C613 10uF 16V TXE2 C606 0 01UF L601 BEAD 120 PHS PD26 PD12 PD30 100uF C6...
Page 35: ...403 1K PS3 VR501 10 K OP W R239 4 7K OP HDATA0 C401 22uF R300 10 K R402 620 12V A5V U300 24LC04B 5 6 7 8 1 2 3 4 SI SCK WP VCC A0 A1 A2 VSS GND R321 0 OP GND C954 1000PF VGA_CON GND KEY 5V GND C316 22...
Page 36: ...84 1 2 3 GND Vout Vin GND C952 1000PF GND GND GND 5V J1 12V POWER GND F A5V D5V JP301 1 2 3 D300 B320 U304 LM2596S 5 0 Si8050 TO263 1 5 4 3 2 VIN ON FBK GND Vout GND 5V U306 4431 1 2 3 4 8 7 6 5 S1 S2...
