Trouble Shooting Guide; Power Board - LG 42PG1000 Service Manual

1. Power Board

1-1. The whole flowchart which it follows in voltage output state
Start check
Doesn't the
screen whole come
out?
No
Doesn't the
low pressure output
come out?
No
Doesn't the
high tension output
come out?
No
Does
high tension
output voltage Drop
occur?
No
Manufacture enterprise
meaning of a passage
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Only for training and service purposes

TROUBLE SHOOTING GUIDE

Yes Is it identical
with Power Off
condition?
Yes
1. Check the Power Off
condition.
Doesn't the
Yes
St-by 5V signal
come out?
Yes
3. Check the St-by 5V
signal circuit.
Doesn't the
Yes
VSC signal Vs-ON
come out?
Yes
7. Check the VSC Vs-ON
signal
When the
Y, Z B/D Module
Yes
input connector is remove,
does Power Board hightension
output voltage Drop
occur?
Yes
9. Check the Power
Board Output high
tension circuit
No
Is the Interface
signal operated?
Yes
2. Check the Interface
signal condition.
Doesn't the
No
5V Monitor signal
come out?
Yes
4. Check the 5V Monitor
signal circuit.
Doesn't the
No
Vs, Va voltage output
come out?
Yes
8. Check the Vs, Va
voltage output circuit.
When the
Y B/D Module
No
input connector is
removed, does output
voltage drop
occur?
Yes
10. Check the Z B/D
Module output circuit
- 15 -
Doesn't the
No
VSC signal RL-ON
come out?
Yes
5. Check the VSC RL-ON
signal.
Doesn't the
VSC low pressure
output come out?
Yes
6. Check the VSC low
pressure output
When the
Z B/D Module
No
input connector is
removed, does output
voltage Drop
occurs?
Yes
11. Check the Y B/D
Module output circuit
LGE Internal Use Only
No