LG 32LC7D Service Manual page 16

3. Protect Mode
(1) Symptom
1) After lighting up once, it does not discharge
minutely from module.
2) The rely falls.(there is an audible "click")
3) The color of the front LED turns from green to red.
(2) Procedure check
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 the output Low/High voltage normal
except for Stand-by 5V?
No
After connecting each connector do
they operate normally?
No
Is the appropriate Fuse(FS101,FS102)
on the Y-B/D normal?(Replace if open)
No
Is the appropriate Fuse (FS1, FS2) on
Z-B/D? (replace if open)
Is the output voltage normal after
No
removing P1, 2, 3, 4, 5 connectors of
the X-B/D?
Is the output voltage normal after
No
removing P1, 2, 4, 9, 10 connectors of
the Ctrl-B/D?
No
Is the output voltage normal after
removing P900, P901 of VSC Board?
No
After a COF crisis for each board, check the normal operation. For normal operation,
corresponding COF failure means the module should be relaced.
No
Replace the Power Board.
Yes
Is the output voltage
Yes
normal after removing
Is the output voltage
Yes
normal after removing
If the output voltage is normal after removing
Yes
the P1, P2, P3 : Replace the right X-B/D
If the output voltage is normal after removing
the P4, P5 : Replace the left X-B/D
Yes
Yes
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Replace the connector.
Yes
P103 connector of
Y-B/D?
Yes
P1 connector of
Z-B/D?
Replace the
X-Board.
If it operates normally after removing the
P900, P901 : Replace the VSC Board
Replace the
Y-Board.
Replace the
Z-Board.