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- 13 -

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

NoNo

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

- 14 -

T801: Vs Trans

T901: Va Trans

T112: Low Voltage Trans

T501: ST-BY Trans

T601: PFC Inductor

- 15 -

1) Doesn’t minute discharge at module. 
2) Non does not come in into the front LED. 

Is plug in power cord?

Plug in power cord.

Yes

No

Is the Line Filter and Power

Board Cable connected?

Connect the Cable.

Yes

No

Is the Fuse(F101) on

Power Board normal?

Replace the Fuse.

Yes

No

Is the Power Board and 7P of

VSC Board Cable connected?

Connect the Cable.

Yes

No

After the cable connect is removed
to Power Board(except the CN101
connection cable), the AC voltage
marking is authorized on manual.
When ST-BY 5V is not operated,
replace Power Board.

- 16 -

1) After once shining, it does not discharge minutely

from module.

2) The Rely falls.(The sound is audible “click”) 
3) It is converted with the color where the front LED 

is red from green.

Is the Power Board

normal ?

Replace Power

Board.

Is output the normality Low/High

voltage except Stand-by 5V?

Yes

No

No

Is the each connector

normal?

Replace the

connector.

Replace

Y-Board.

After connecting well each connector,

the normality it operates? 

Yes

No

No

Is the Ctrl Board

normal?

Replace

X-Board.

Is the output voltage normal after

remove P1, 2, 4, 9, 10 connector of

Ctrl-B/D?

Yes

No

Yes

Is the Y-Board

normal?

Is the output voltage
normal after remove

P5, P6 connector of

Y-B/D?

Is the Fuse(FS2) on Y-B/D normal?

(In case of open is replace)

Yes

No

Yes

Yes

Replace

Z-Board.

Is the Z-Board

normal?

Is the output voltage
normal after remove

P1 connector of Z-

B/D?

Is the Fuse (FS1, FS2) on Z-B/D

normal? (In case of open is replace)

Yes

No

Yes

Is the X- Board

normal?

Is the output voltage normal after

remove P1, 2, 3, 4, 5 connector of

X-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.

Yes

No

Yes

Is the 

VSC Board normal?

Is the output voltage normal after

remove P1001, P1100?

After crisis COF of each board, check the normality operates.
If in case normality operates, correspondence COF Fail is
replace the module.

After remove P1001, 1100 normal
operation: Replace VSC Board.

Yes

No

Is the COF of X, Y, Z

normal ?

No

Yes

Yes