Tuesday, November 06, 2012

LG - PLASMA_DEFECTS_CHECKS_RECTIFICATION



DEFECT:  VERTICAL BAR


Check the COF [Chip On Film] connector.  If not connected well will make a BAR defect.





Confirm whether COF was torn.  Check the input of COF resistor and IG

EG:  COF 6 torn partially.

Tearing;

COF RESISTOR CHECKING

Check the both side of the resistor with a digital multimeter.
If resistor is normal, the value will be 10.2 ~ 10.8 Ohms.
If open, the value will be infinite.



CHECKING ADDRESS COF INPUT OF RESISTOR AND IC

  • Inside IC, there are 4 ea diodes which separated in 2 series. [Input 2, Output 2]
  • Contact DMM (-) termianal to a right terminal of condenser.[GND], and DMM (+) terminal to a right terminal of IC, normal value 0.66.
  • Contact DMM (-) terminal to output terminal of resistor, and (+) terminal to a right terminal of IC.  Normal value 0.73. 


VERTICAL DEFECT [LINE]

In case of 1 line open or short , check foreign substances in COF connector. First blow up foreign substances with your mouth. And then if the same line appears, replace the panel.
 Line Open or Short.


ONE LINE OPEN


ONE ELECTRODE OPEN


LINE OPEN OR SHORT WITH SAME DISTANCE:  This is MCM of Ctrl b/d defect.  Repalce the ctrl b/d


MCM [Multi Chip Module]


Contd

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