- Change the Vpp Pin into ANODE and GND Pin into CATHODE and then test the Diode with forward or reverse direction.
SCREEN DISPLAY PROBLEM FOR SCAN FFC
- It’s may be a problem between Scan FFC and Y B/D.
- Check the connection of Y B/D and Scan COF.
- If the Scan IC is failed, replace the Y DRV B/D.
SCREEN DISPLAY FORM
THE SCREEN HAS A VERTICAL LINE WITH REGULAR GAP [A vertical stripe flash at especial color]
- This is a problem about control B/D.
- Replace Control B/D.
SCREEN DISPLAY FORM
A DATA COPY IS HAPPENED INTO VERTICAL DIRECTION
- In this case, it’s due to incorrect marking of scan wave.
- Replace a Y DRV B/D or Y SUS B/D.
THE SCREEN HAS ONE OR SEVERAL VERTICAL LINES
In this case, It isn’t a problem about controller B/D or
XB/D.
It may cause followings.
- It’s out of order a panel
- Open or short of DATA COF FPC attached panel
- It’s out of order a DATA COF attached panel
- Replace Module.
Screen display form
SCREEN HAS ONE OR SEVERAL HORIZONTAL LINES
In this case, it isn’t a problem about controller B/D or
XB/D.
It may cause followings.
- It’s out of order a panel
- Open or short of SCAN FPC attached panel
- It’s out of order a SCAN IC attached panel
- Replace Y DRV B/D
THE SCREEN DISPLAYS INPUT SIGNAL PATTERN, BUT THE BRIGHTNESS IS DARK.
- In this case, Z B/D operation isn't complete.
- Check the power cord of Z B/D.
- Check the connector of Z B/D and Controller B/D.
- Replace the Controller B/D or Z B/D.
DISPLAYS OTHER COLORS PARTIALLY ON FULL WHITE SCREEN OR HAPPENS DISCHARGE PARTIALLY ON FULL BLACK SCREEN
- Check the declination of Y B/D set up, set down wave.
- Check the declination of Z B/D ramp wave.
- Measure each output wave with oscilloscope (more than 200MHz) and compare the data with below figure data.
- Adjust the Y B/D set up(Test-up:B/C - VR1)/setdown(Test-down:D uSEC - VR2) and Z B/D ramp(Tramp:F/G - VR3) declination by changing VR1/VR2/VR3.
- Measuring Point of Y B/D : P4 (Connector P4 36 pin)
- Measuring Point of Z B/D : B37 (SUS_OUT).
CENTER OF THE SCREEN IS DARKER THAN A EDGE OF THE SCREEN AT FULL WHITE PATTERN
- In this case, it’s a problem about Z B/D ramp wave.
- Check the connection cable of Z B/D and CTRL B/D.
- Replace the Z B/D.
DOESN'T DISPLAY A SPECIFIED BRIGHTNESS AT SPECIFIED COLOR
- Check the connector of CTRL B/D input signal.
- Replace the CTRL B/D.
DATA-COF IC CHECK
It Generates Unusual Pattern of Data COF IC unit
- In case of generating unusual pattern of Data COF IC unit as below picture, there is problem in the check that is input into Data COF IC
- In case of <case 1, 2, 3> - confirm the connection of Data COF connector - replace the relevant X B/D
- In case of <case 4, 5> - confirm the connector that is connected from CTRL to X B/D - Replace relevant XB/D or CTRL B/D
REGULAR STRIPE GENERATED ABOUT QUANTITY OF ONE DATA-COF IC OR MORE
- In case of generating regular stripe about the quantity of one Data COF IC, there is problem at the output of output flatworm of X B/D. In case of generating regular stripe about the quantity of two Data COF ICs, that means the data which is conveyed from CTRL B/D is not conveyed well.
- Confirm the XB/D connection connector plugged in well. Correspond to unusual screen.
- Replace relevant XB/D or CTRL B/D.
Relationship between screen and X B/D
Screen X B/D
Left Bottom of the Screen 4/7 ó Right X B/D
Right Bottom of the Screen 3/7 ó Left X B/D
Screen Display Form.
