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Does the power LED light 
up or flash in red or green?

Fully insert the connector.

Go to "Main PWB check".

Go to "Checking the lamp 
light-up".

Go to "DMD system 
check".

Does the set function with 
its keys or the remote 
controller?

Has P1701 come off or is it 
loose?

END

Go to "RGB and 
component signal check".

Go to "VIDEO input 
check".

Go to "S-VIDEO input 
check".

Check PHOTO SENSOR 
circuit.

Lamp does not turn on or it 
turns off in a short time.

Nothing is displayed or 
white vertical line noise 

Colors are not displayed 
normally. Color deviation 
and color fluctuation occur.

Are RGB and component 
input displayed normally?

Is VIDEO input displayed 
normally?

Is S-VIDEO input 
displayed normally?

YES

NO

Is 6 V applied to TL1702

and 13 V to TL1703?

Is approx. 6 V applied to

TL1742?

YES

Is 1.5 V applied to

TL1741?

Go to "Power supply

ballast PWB check".

NO

Check IC1742 and

peripheral circuits.

NO

Check IC1741 and

peripheral circuits.

YES

Is 3.3 V applied to

TL1762?

NO

Check IC1763 and

peripheral circuits.

Is 2.5 V applied to

TL1763?

NO

Check IC1762 and

peripheral circuits.

YES

Is 5 V applied to TL1791?

NO

Check IC1791 and

peripheral circuits.

YES

Is 3.3 V applied to

TL1792?

NO

Check IC1792 and

peripheral circuits.

YES

Is 12 V applied to

TL1761?

NO

Check IC1761 and

peripheral circuits.

YES

Main PWB check

YES

Is 3.3 V applied to pin(1)

of IC1743?

NO

Check IC1743 and

peripheral circuits.

YES

Is 3.18 V applied to pin(1)

of IC2001?

NO

Check IC2001 and

peripheral circuits.

YES

Is 3.3 V applied to pin(3)

of S2001?

NO

Check that it is set to the N

side. Or remove S2001.

YES

Is rectangular wave of 50

MHz sent to X2251 pin(3)?

NO

YES

Check IC2002, IC2262,

IC2263 and peripheral

circuits.

Check X2251 and

peripheral circuits.

Check P2501 for breakage 
and solder crack and 
peripheral resistance for 
solder crack.

Check SC9101 for 
breakage and solder crack.

Is there any vertical stripe 
(block noise) on the 

Is the screen all black?

Is approx. 7 V applied to 
TL9303?

Is 3.27 V applied to IC2231 
pin(1) and 1.8 V to TL2231?

Is 400 MHz on IC2241 pin 
(20)?

Is approx. 26 V applied to 
TL9301?

Is approx. -26 V applied to 
TL9302?

Check IC2231, IC2201, 
and their peripheral 
circuits.

The main PWB and DMD 
PWB are in poor contact. 
Check the contact surface 
for dirt and smear.
Check the DMD connector 
for breakage.
Reassemble the DMD, 
optical mechanism, and 
DMD PWB.

Check IC2241 and 
peripheral circuits.

Check IC9301 and 
peripheral circuits.

Check peripheral circuits of 
IC703.

Is 13 V applied to pins (3) 
and (4) of the connector 
P704?

Is DC voltage of 380 V 
applied to both ends of 
C704?

Check circuits R766 and 
after or replace R766.

Is R766 in the OPEN 
status?

Is pin (11) of the connector 
P704 at "H"?

Are connectors P704 and 
CN901 fully inserted?

Is 6 V applied to pins (7) 
and (8) of the connector 
P704?

Securely insert the 
connectors.

Check peripheral circuits 
of IC902.

Is LAMP-EN/SYNC signal 
properly sent to pin (14) of 
the connector P704?
(Refer to the waveform 
chart 1.)

Are GATE waveforms of 
Q901 and Q903 
appropriate?
(See waveform diagram 

8.)

Does the lamp turn on?

Check the main PWB.

Check the main PWB.

Check the main PWB.

Check the ballast PWB.