HP L1940T SERVICE MANUAL 19” LCD Monitor L1940T Series THESE DOCUMENTS ARE FOR REPAIR SERVICE INFORMATION ONLY. EVERY REASONABLE EFFORT HAS BEEN MADE TO ENSURE THE ACCURACY OF THIS MANUAL; WE CANNOT GUARANTEE THE ACCURACY OF THIS INFORMATION AFTER THE DATE OF PUBLICATION AND DISCLAIMS RELIABILITY FOR...
HP L1940T 1.Monitor Specifications Driving system TFT Color LCD Panel M190E5-L0A Active Area 376.32(H) x 301.056(V) (19.0") Pixel pitch 0.294( H )x 0.294mm( V ) LCD Panel Viewing Angles(Min / TYP) H:120/140; V:110/130 Response time (typ.) < 8 ms Brightness...
HP L1940T 2. LCD Monitor Description The LCD Monitor will contain main board, power board, key board and which house the flat panel control logic, brightness control logic and DDC. The power board will provide AC to DC Inverter voltage to drive the backlight of panel and the main board chips each voltage.
HP L1940T 3.2 Control Buttons Power Indicator: Green — Power On mode. Orange — Power Saving mode. Blank —Power Off Mode. Auto Adjust : Activates the auto adjustment feature for optimum image. Menu : Opens the ON-Screen Display(OSD) menu. Minus (–) : 1、If OSD is on, press to navigate backward through the OSD menu features and decrease adjustment levels.
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HP L1940T Service Mode Press and hold the “Menu” button, Power off -> on “Power”,then into the service mode, Press “menu” button to bring to OSD menu for confirmation as below: Factory Mode 1、 Turn off monitor. 2、 [ Push “Auto Adjust” and “+ (plus)”and hold them at the same time ]+ [ Press power “Power” button untill comes out “windows screen”...
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HP L1940T Menu icons Control Icon Brightness Contrast Auto Adjustment Image Control Color Custom Color Language Management OSD Control Information Factory Reset Default Video Input Horizontal Position Vertical Position Clock Clock Phase Power Saver Mode Display Power-On Status Display Sleep Timer...
HP L1940T 4. Input/Output Specification 4.1 Input Signal Connector Analog Connector Pinout Mnemonic Signal Mnemonic Signal Red Video +5 V +5 V (from PC) Green Video Sync Ground Blue Video None None DDC Data GND / Cable Detect Horizontal Sync...
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HP L1940T DVI-D Digital Connector Pins Pin. Mnemonic Signal Pin. Mnemonic Signal TX 2 - TMDS Negative differential input, channel 2 TX 3 + TMDS Data 3 + TX 2 + TMDS Positive differential input, channel 2 +5V Power SHLD 2 / 4...
HP L1940T 5. Panel Specification 5.1 General Feature - Wide viewing angle. - High contrast ratio - Super fast response time - High color saturation - SXGA (1280 x 1024 pixels) resolution - DE (Data Enable) only mode - LVDS (Low Voltage Differential Signaling) interface...
HP L1940T 8. Troubleshooting Problem Possible Cause Solution Screen is blank. Power cord is disconnected. Connect the power cord. Power switch is turned Off. Turn on the power. Video cable is improperly connected. Connect the video cableproperly. Screen blanking utility is active.
HP L1940T 12. Maintainability Equipments and Tools Requirement 1、Multi-meter. 2、Oscilloscope. 3、Pattern Generator. 4、DDC Tool with an IBM Compatible Computer. 5、Alignment Tool. 6、LCD Color Analyzer. 7、Service Manual. 8、User Manual.
= 313±20, y = 329 ±20, Y= 150 cd/m 3. Into factory mode of HP L1940T [ Push “Auto Adjust” and “+ (plus)”and hold them at the same time ]+ [ Press power “Power” button untill comes out “windows screen”...
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HP L1940T 2. The chroma 7120 will show x = 313 ±20, y = 329 ±20, Y = 180 cd/m 3. Switch the chroma 7120 l to RGB MODE ( with press “MODE” button to change ) 4. Adjust the RED of color 6500K on factory window until chroma 7120 indicator reached the value R=100 5.
HP L1940T 14. Check List after replacing LCD Main board Check if white-balance is within the specs after replacing Main board and panel, then re-writing DDC is necessary. 14.1 Check white-balance The white-balance value for each common color temperature: 9300 º K: x=283± 20 ; y = 297± 20;...
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HP L1940T 2. Select the DDC2Bi as the communication channel. As shown in Fig. 12. 3. Click OK button to confirm your selection. 4. Click icon (Read EDID function) to read DDC EDID data from monitor. The EDID codes will display on screen as...
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HP L1940T Step 3: Modify DDC data (verify EDID version, week, year) Click (new function) icon from the tool bar, bring up Step 1 of 9 as shown in Fig. 14 . EDID4.6 DDC application provides the function selection and text change (select & fill out)from Step 1 to Step 9.
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HP L1940T 2. Click Next , bring up Fig.16. 3. Click Next , bring up Fig.17.
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HP L1940T 4. Click Next , bring up Fig.18. 5. Click Next , bring up Fig.19.
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HP L1940T 6. Click Next , bring up Fig. 20. In this step, please confirm the Descriptor Data Type is Monitor Range Limits, and all the items are same as below. 7. Click Next , bring up Fig. 21.
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HP L1940T 8. Click Next , bring up Fig. 22. - Click Finish to exit the Step window. - Serial number can be filled up at this moment (for example,TWP318Q001). NOTE: You must modify the Serial NO. In step 9, otherwise the Serial NO. In OSD Couldn't be modified correctly.
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HP L1940T 2. Access Factory Mode 1). Turn off monitor. 2). [Push "Auto Adjust " and" +(plus)"and hold them at the same time ] + [Press power "Power " button untill comes out "Windows screen"] => then release all button, then press "Menu" button, wait until the OSD menu with Characters "F"...
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HP L1940T Sometimes, you may need to save DDC data as a text file for using in other IC chip. To save DDC data, follow the steps below: 1. Click (Save) icon (or click "file"-> "save as") from the tool bar and give a file name as shown in Fig. 25. The file type is EDID46 file (*.ddc) which can be open in WordPad.
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HP L1940T Step 2: Read DDC data from monitor 1. Click icon as shown in Fig. 11 from the tool bar to bring up the Channels "Configuration Setup" windows as shown in Fig. 2. Select the DDC2Bi as the communication channel. As shown in Fig. 29.
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HP L1940T 3. Click OK button to confirm your selection. 4. Click icon (Read EDID function) to read DDC EDID data from monitor. The EDID codes will display on screen as shown in Fig. 30. Step 3: Modify DDC data (verify EDID version, week, year) Click (new function) icon from the tool bar, bring up Step 1 of 9 as shown in Fig.
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HP L1940T 2. Click Next , bring up Fig. 33. Fig. 33 Fig. 34 3. Click Next , bring up Fig. 34. 4. Click Next , bring up Fig. 35. 5. Click Next , bring up Fig. 36. 6. Click Next , bring up Fig. 37.
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HP L1940T 8. Click Next , bring up Fig. 39. - Click Finish to exit the Step window. - Serial number can be filled up at this moment (for example, TWP318Q001). NOTE: You must modify the Serial NO. In step 9, otherwise the Serial NO. In OSD Couldn't be modified correctly.
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HP L1940T 3) Push Menu to exit OSD menu. 3. Click (Write EDID) icon from the tool bar to write DDC data.Then the screen will be black for 5-10 seconds, when the screen recovers ,DDC data will be finished Writing.
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HP L1940T 1. Click (Save) icon (or click "file"-> "save as") from the tool bar and give a file name as shown in Fig. 46. The file type is EDID46 file (*.ddc) which can be open in WordPad. By using WordPad, the texts of DDC data & table (128 bytes, hex code) can be modified.
Part No. for TPV Description Quantity Unit 007G 7 L151 COMPOUND PALLET 0.025 015G6344 1 AC BRACKET 1.000 023G3178690 7A HP LOGO 7121-8115 1.000 034G6402 EY B REAR COVER 1.000 037G6057 2 HINGE 1.000 040G 152509 RECYCLE LABEL 1.000 040G 152512 RECYCLE LABEL 1.000...
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HP L1940T 1603 088G 350 1 TN USB CONN 1.000 1602 088G 351 2B CL USB CONN 1.000 1602 088G 351 2B TN USB CONN 1.000 1203 088G 35315F H D-SUB 15PIN 1.000 1203 088G 35315F HJ SOC SUBD H 15P F 1.000...
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HP L1940T 3634 061L0603000 RST SM 0603 JUMP MAX 0R05 R 1.000 3614 061L0603000 RST SM 0603 JUMP MAX 0R05 R 1.000 3606 061L0603000 RST SM 0603 JUMP MAX 0R05 R 1.000 3605 061L0603000 RST SM 0603 JUMP MAX 0R05 R 1.000...
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HP L1940T 5605 071GP57K101 TA IND FXD 1206 EMI 100MHZ 100R R 1.000 5606 071GP57K101 TA IND FXD 1206 EMI 100MHZ 100R R 1.000 5607 071GP57K101 TA IND FXD 1206 EMI 100MHZ 100R R 1.000 5601 071GP57K101 TA IND FXD 1206 EMI 100MHZ 100R R 1.000...
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HP L1940T 6207 093G 64 33 DIO SIG SM BAV99 (PHSE)R 1.000 6207 093G 64 33 DIO SIG SM BAV99 (PHSE)R 1.000 6207 093G 64 33 DIO SIG SM BAV99 (PHSE)R 1.000 6208 093G 64 33 DIO SIG SM BAV99 (PHSE)R 1.000...
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HP L1940T 1936 077G 604 1 FD SWI TACT 1P 1POS 12V V 1MM5 R 1.000 6931 081G 14500 KB LED VS SM KAA-3528YSGC (KIEL)R 1.000 715G1855 1 KEY BOARD 1.000...