LG 50PC1D Series, Service Manual

Page: 17 / 58

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TROUBLE SHOOTING GUIDE
1. Power Board
1-1. The whole flowchart which it follows in voltage output state
Start check
Manufacture enterprise
meaning of a passage
1. Check the Power Off
condition.
Doesn't the
screen whole come
out?
Is it identical
with Power Off
condition?
Yes
Yes
No
No
No
No
No
2. Check the Interface
signal condition.
Is the Interface
signal operated?
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
Yes
No
4. Check the 5V Monitor
signal circuit.
Doesn't the
5V Monitor signal
come out?
Yes
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
Yes
Does
high tension
output voltage Drop
occur?
When the
Y B/D Module
input connector is
removed, does output
voltage drop
occur?
When the
Y, Z B/D Module
input connector is remove,
does Power Board hightension
output voltage Drop
occur?
Yes No No
9. Check the Power
Board Output high
tension circuit
Yes
10. Check the Z B/D
Module output circuit
Yes
When the
Z B/D Module
input connector is
removed, does output
voltage Drop
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?
Yes
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