No Raster - LG 42PX3RV Service Manual

4. No Raster

(1) Symptom
DoesÕt minute discharge at module.
¯
It maintains the condition where the front LED is green.
¯
(2) Check following
Is the Power Board
normal?
Yes
Is the each connector
normal?
Yes
Is the Y- Board
normal?
Yes
Is the Z- Board
normal?
Yes
Is the X- Board
normal?
Yes
Is the Ctrl Board
normal?
Yes
Is the VSC Board
normal?
Yes
Is the COF of X, Y, Z
normal?
No
Is output the normality Low/High
voltage except Stand-by 5V?
No
After connecting well each connector,
the normality it operates?
No
Is the Fuse(FS2) on Y-B/D normal?
(In case of open is replace)
No
Is the Fuse(FS1, FS2) on Z-B/D
normal? (In case of open is replace)
Is the output voltage normal
No
after remove P1, 2, 3, 4, 5
connector of X-B/D?
Is the output voltage normal
No
after remove P1, 2, 4, 9, 10
connector of Ctrl-B/D?
No
Is the output voltage normal
after remove P1001, P1100?
No
After crisis COF of each board, check the normality operates.
If in case normality operates, correspondence COF Fail is
replace the module.
No
No
Yes
Yes
Yes
Yes
Yes
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Replace Power
Board.
Replace
connector.
Is normal the output
Yes
voltage after remove
P5, P6 connector of
Y-B/D?
Is normal the output
Yes
voltage after remove
P1 connector of
Z-B/D?
After remove P1, P2, P3 output voltage
normality: Replace Right X-B/D
After remove P4, P5 output voltage
normality: Replace Left X-B/D
Replace
X-Board.
After remove P1001, P1100 normal
operation: Replace VSC Board
Replace
Y-Board.
Replace
Z-Board.