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4. Troubleshooting
4. Troubleshooting
4-1. Troubleshooting
1. Before troubleshooting, setup the PC `s display as below. · Resolution: 1920 x 1080 · H-frequency: 75 kHz · V-frequency: 60 Hz 2. If no picture appears, make sure the power cord is correctly connected. 3. Check the following circuits. · No raster appears: Function PBA. Main PBA. IP-Board · 5V develop but no screen : Main PBA · 13V, 5V does not develop: IP-Board, Main PBA
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4. Troubleshooting
4-2. When the Power Does Not Turn On
Symptom - The LED on the front panel of the monitor does not work when the power is connected and the Power button is pressed. - Check if the Power switch on the rear panel of the monitor has been turned on. - Check the SMPS fuse and the IP-Board output power. Major checkpoints - Check the connection between the IP-Board and the Main Board inside the monitor. - Check the power part of the Main Board and check if a similar symptom appears at another output terminal.
CN600
IC203
Diagnostics Check the connection status of the Function assy.
Main Board Front
Can DC 5V be measured on pins 6, 7 of the CN600 connector when pins 3, 4, and 5 are 0V? Yes Can DC 3.3V be measured on pin 3 of the IC203 when pin 1 is DC 5V? Yes Check and replace the main board related to the scaler. Caution
No
Replace the IP board.
No
Check the circuits related to the IC203.
Make sure to disconnect the power before working on the IP board.
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4. Troubleshooting
4-2-1. Circuit Diagram and Waveform for Power Failures
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4. Troubleshooting
4-3. When a blank screen is displayed (Analog)
Symptom - The LED power is on but no picture is displayed on the screen when the D-SUB cable is connected - Even though the LED power turns on, the screen is blank when connecting the VGA cable. Major checkpoints - Check the D-sub cable connections. - Check whether the LVDS cable is connected correctly to the panel. - Check whether the lamp connector of the panel is connected correctly to the IP board.
CN400 IC202 X200 R106 R110 R121
R115 R116
Main Board Front Check the signal cables and their connections. Yes Diagnostics Check if X200 is oscillating normally. Yes Check if R, G and B inputs are measured at R106, R110 and R121. Yes Check if Hsync and Vsync are measured at R115 and R116. Yes Check if Hsync and Vsync are measured at pins 32 and 33 of IC202. Yes Do output signals appear at pins 8 to 30 of CN400? Yes Is DC 5V measured at pins 1, 2, and 3 of the CN400? Yes Replace the LCD panel. No Check the +5V_Panel signal and the BL_EN signal. No Check the circuit around IC202. No Check the input part. No Check the input part. No Check and replace related circuits if necessary.
No
Check the input part.
Caution
Make sure to disconnect the power before working on the IP board.
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4. Troubleshooting
4-3-1. Circuit diagrams and waveforms (analog) when a blank screen is displayed on the monitor
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4. Troubleshooting
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4. Troubleshooting
4-4. When a Blank Screen Is Displayed (DVI)
Symptom - The LED power is on but no picture is displayed on the screen when the DVI cable is connected. - Check if the LED power turns on but no screen is displayed when connecting the DVI cable Major checkpoints - Check if the DVI cable has been connected. - Check if the LVDS cable has been properly connected to the LCD panel. - Check if the Inverter board has been connected properly to the lamp connector of the LCD panel.
CN400 IC202 X200 R142~R151
Main Board Front Diagnostics Check the signal cables and their connections. Yes Check if X200 is oscillating normally. Yes Check if R, G and B signals are measured at R142~R145, R148~R151. Yes Check if the output signal appears at pins 8 to 30 of CN400. Yes Replace the LCD panel. Caution Make sure to disconnect the power before working on the IP board. No Check the circuit around IC202. No Check the input part. No Check and replace related circuits if necessary.
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4. Troubleshooting
4-4-1. Circuit diagrams and waveforms (DVI) when a blank screen is displayed on the monitor
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4. Troubleshooting
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4. Troubleshooting
4-5. Error Examples and Actions
Error Appearance Symptoms and Actions Symptom: DVI signals are not recognized. Cause: This error occurs because the PC cannot recognize the mode information since the DVI DDC is not input to the monitor. Action: Input the DVI DDC. Remarks *On how to input DDC, refer to the training manual.
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4. Troubleshooting
4-6. Adjustment
4-6-1. Service Adjustment Conditions
1. Precautions before a Service Adjustment. 1) Check whether the devices for the service adjustment are operating normally. 2) Secure a space that is sufficiently wide for disassembling the monitor. 3) Prepare a soft mat on which the monitor will be disassembled. 2. Entering Service Mode. Entering: Exiting: Menu Power OFF Brightness 0 Power ON Contrast 0 Hold down the Enter button for five (5) seconds.
3. Auto Color Adjustment Use a 16 gray-scale or gray-black-mixed pattern for the video input. 1) For the OSD Language, select the language at the top.. 2) Press and hold the OSD "(Enter/Source)" for 5 seconds.
4-6-2. Firmware Download
You have to complete the post-operation using a MICOM Jig (RS232 Jig) after replacing the Main Board. You can update the Micom using a MICOM Jig (RS232 Jig).
Requirements
- The following devices are required for adjusting the monitor - A Computer with Windows 95, 98, 2000, XP or NT. - MTI-2059 DDC Manager Jig - RS232 Jig
Entering the Micom Code
- You have to complete the operation using the DDC Manager after replacing the Main Board. - Connect devices as shown below. - You can update the Micom using the DDC Manager.
Connect to the Parallel Board
DDC Manager RS232 JIG
CN101 Connect to the Main Board (CN101)
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4. Troubleshooting
Entering the Micom Code
1. Run "winDDC" and select "MSTAR", "TSUMxxx", "DSUB15(Analog)", "PMC25LV020" step by step.
2. Click "Load File" and select the latest code in the format of "*.hex".
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4. Troubleshooting 3. Click "Program"
Entering the EDID
- You can update the EDID/DDC (Analog / DVI / HDMI) using the DDC Manager Jig. - Connect the devices as shown below
MTI-2059 DDC Manager Signal Connector Connect to the Monitor (D-SUB/ DVI/HDMI)
-
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4. Troubleshooting
Entering the EDID
1. Install the Winddc.exe program onto the PC. 2. Click the Winddc icon. 3. Select Open. 4. Select Port #1 5. Open a DDC file. *File Name "SM2494HMA.ddc" Analog DDC "SM2494HMD.ddc" Digital DDC "SM2494HMH.ddc" HDMI DDC 6. Click Next (OK).
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4. Troubleshooting 7. Enter the Monitor S/N and press Enter. Enter for Analog, Digital and HDMI.
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4. Troubleshooting
4-6-3. Service Function Spec.
1. 1. Set the Brightness and Contrast to 0. 2. Press and hold the Enter and Source keys. 3. The SVC Function OSD appears. *To exit from the SVC Function OSD, you have to turn the power off.
Panel Information
Software Version MICOM Checksum
The SVC Function OSD consists of a 103 (Horizontal) x 82 (Vertical) Grid. The SVC Function OSD consists of Panel Information, the Software Version and the Micom Checksum.
Navigating Menus
1. Press the () key to move up and press the () key to change the value of a selected.
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4. Troubleshooting
Replacing the Panel
When replacing the panel: After replacing the panel, select the Panel Ch. No. item and press and hold the MENU key for 5 seconds. The Panel Ch. No. increases by 1 and the Panel On Time is reset to 0. At the same time, the Panel Cycle is also reset to 0.
Other Functions
1. Auto Auto : On / Off 2. PixelShift : On / Off 3. Country : English / Korean / Chinese / Japanese 4. HDCP HP-DVI : On / Off 5. HDCP HP-HDMI : On / Off 6. HotPlug Time : 5~50 (Default 9 : 0.9sec)
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4. Troubleshooting
Memo
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