CONFIDENTIAL 1 Precautions Follow these safety, servicing and ESD precautions to prevent damage and to protect against potential hazards such as electrical shock. 1-1 Safety Precautions 1-1-1 Warnings For continued safety, do not attempt to modify the (READING SHOULD circuit board. NOT BE ABOVE 0.5mA) Disconnect the AC power and DC Power Jack before servicing.
CONFIDENTIAL 1 Precautions 1-2 Servicing Precautions WARNING: An electrolytic capacitor installed with the wrong polarity might explode. Caution: Before servicing units covered by this service manual, read and follow the Safety Precautions section of this manual. Note: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions, always follow the safety precautions.
CONFIDENTIAL 2 Product Specifications 2-2 Pin Assignments Sync 15-Pin Signal Cable Connector Type Separate Composite Sync-on-green Pin No. Green Green Green + H/V Sync. Blue Blue Blue GND (DDC Return) GND (DDC Return) GND (DDC Return) GND-R GND-R GND-R GND-G GND-G GND-G GND-B...
CONFIDENTIAL 2 Product Specifications 2-3 Timing Chart This section of the service manual describes the timing that the computer industry recognizes as standard for computer-generated video signals. Table 2-1 Timing Chart Mode VESA VGA1/70 Hz VGA3/60 Hz VGA2/70 Hz 800/60 Hz 640/72 Hz 640/75 Hz 800/56 Hz...
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CONFIDENTIAL 2 Product Specifications Table 2-1 Timing Chart (Continued) Mode VESA 640/67 Hz 832/75 Hz 1024/60Hz 1024/70Hz 1024/75Hz 800/72 Hz 800/75 Hz 1024x768 1024x768 1024x768 640 x 480 832 x 624 800 x 600 800 x 600 Timing fH (kHz) 35.000 49.726 48.077...
CONFIDENTIAL 3 Disassembly and Reassembly This section of the service manual describes the disassembly and reassembly procedures for the GH15H* monitor. WARNING: This monitor contains electrostatically sensitive devices. Use with caution when handling these components. 3-1 Disassembly Cautions:1. Disconnect the monitor from the power source before disassembly. 2.
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CONFIDENTIAL 3 Disassembly and Reassembly 3-2 Replacement Order of Lamp Assemblies 1. After confirm there is nothing on the disk Turn the LCD module over and put it on a flat desk set to the ground. 2. Push down the stopper and slide the lamp unit.
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CONFIDENTIAL 3 Disassembly and Reassembly 4. Please fix the new lamp units on the LCD module : opposite process 2 and 3 Replacement of lamp unit should be done at the power off state and recommanded clean bench condition. 3-3 Reassembly Reassembly procedures are in the reverse order of Disassembly procedures.
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CONFIDENTIAL 3 Disassembly and Reassembly Memo GH15H*...
CONFIDENTIAL 4 Troubleshooting Notes: 1. Before troubleshooting, setup the PC’s display as below. • Resolution: 1024 x 768 • H-frequency: 48 kHz • V-frequency: 60 Hz 2. If no picture appears, make sure the power cord is correctly connected. 3. Check the following circuits. •...
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CONFIDENTIAL 4 Troubleshooting 4-2 No Video Does the H-sync pulse Check CN102. appear at Pin 9 of IC108? Does the H-sync pulse Replace IC108 or appear at Pin 150 of IC105? check its related circuit. Does the V-sync pulse check CN102. appeaer at Pin 30 of IC301? Does the V-sync pulse Replace IC301 or...
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CONFIDENTIAL 4 Troubleshooting 4-3 User Controls Don’t Work Does the DC level change at Check the buttons. Pin 35 and 36 of IC301 when you (SW801~SW808) push the front panel button? Refer to 4-4 No OSD Display. 4-4 No OSD There is video but no OSD.
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CONFIDENTIAL 4 Troubleshooting 4-5 No SOUND Does the DC 12V appear at Pin 15, 16 of IC401 and Check Q403, Q401 and related circuit. Pin 5, 6, 7, 8 of Q403? Does the sound input signal Check CN401 appear at Pin 4 and 9 of IC401? and related circuit.
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CONFIDENTIAL 4 Troubleshooting 4 Troubleshooting 4-6 Microphones Don’t Work Does the PC’s sound Check the PC’s sound program program operate well? and compatibility. Is the connection between the Connect the cable between the PC and monitor secure? PC and monitor. Check the connection between Is the Internal Microphone CN808 on the Audio PCB and the...