Copyright LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
C
2008
- 15 -
TROUBLESHOOTING
1. Power Board
1-1. The whole flowchart which it follows in voltage output state
Start check
Manufacture’s enterprise
meaning of a passage
1. Check the Power Off
condition
Doesn’t the screen
wole come out?
It is
identical with power
off condition?
Yes
Yes
No
No
No
No
No
2. Check the Interface
signal condition.
Is the Interface
signal operating?
Yes
3. Check the St-by 5V
signal circuit.
Doesn’t the low
pressure output
come out?
Doesn’t the
St-by 5V signal
come out?
Yes
No
No
4. Check the 5V Monitor
signal circuit.
Doesn’t the
5V Monitor signal
come out?
No
7. Check the VSC Vs-ON
signal
Doesn’t the high
tension output
come out?
Doesn’t the
VSC signal Vs-ON
come out?
Yes
No
High tension
output Voltage drop it
occurs?
When
remove the Y B/D
Module input connector,
output voltage drop is
occurs?
When remove
the Y, Z B/D Module Input
connector Power Board high
tension output voltage
drop it occurs?
Yes
No
No
9. Check the Power
Board Output high
tension circuit
Yes
10. Check the Z B/D
Module output circuit
Yes
When
remove the
Z B/D Module input
connector,
output voltage drop
is occurs?
11. Check the Y B/D
Module output circuit
Yes
No
8. Check the Vs, Va
voltage output circuit.
Doesn’t the
Vs, Va voltage output
come out?
No
No
No
5. Check the VSC RL-ON
signal.
Doesn’t the
VSC signal RL-ON
come out?
Yes
6. Check the VSC low
pressure output
Doesn’t the
VSC low pressure
output come out?
Yes
