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LC-32DH57E-BK/RU-BK/S-BK

4 – 29

                                             
Do all the fluorescent tubes light up?

YES

Check each fluorescent tube and exchange defective fluorescent 
tubes.

NO

Is 60V supplied to Connector (CN7302) (20-23) pin?

NO

Refer to troubleshooting “No power supply (Front LED does not 
light up)” of a power supply.
Or check a peripheral circuit. (Q7809, Q7807, Q7811, Q7810)

 YES

Is UR12.5V supplied to Connector (CN7302) (10)pin?

NO

Refer to troubleshooting “No power supply” (Front LED does not 
light up) of a power supply. Or check a peripheral circuit.

 YES

Is UR12.5V supplied to (26) pin of IC7700 (INV-CTL)?

NO

Check UR12.5V-line in an INVERTER unit.

YES

Is the STB-ON/OFF signal supplied to (16) pin (or (4) pin of a 
connector (CN7302)) of IC7700 (INV-CTL)?

NO

Check the STB-ON/OFF signal-line in an INVERTER unit.

YES

Is each control signal coming to the connector in INV-UNIT 
(CN7302)?
• ADIM (Tube current setting): (1pin)
• OFL (PWM light control signal input): (2pin)
• ERR (Lamp error output): (3pin) 
• BRT (Light control method identificatio): (5pin)

NO

Check each control circuit.

ADIM-H: Tube current 12mA, L: Tube current 8.5mA
OFL -H: Lamp ON, L: Lamp OFF
ERR -H: Normal, L: Error
REG2-H: External PWM input, L: Analog voltage input

YES

Is [0] displayed as the number of [LAMP_ERROR] in the process 
mode?

NO

Reset the number of [LAMP_ERROR] to the default value in the 
process mode.

YES

Is the drive output signal sent from PIN (31) and (32) of IC7700 
(INV-CTL)?

NO

Check IC7700 (INV-CTL) and the peripheral circuits.

YES

Does the drive output circuit normally work?
(Q7800-Q7806)
(Q7809, Q7807, Q7811, Q7810)

NO

Check which parts are defective.
And exchange the non-conforming articles. 

YES

Is the circuit by the side of secondary operating normally?
(T7903-T7905)

NO

Check defective parts and exchange the inferior products.

YES

Is the circuit by the side of secondary operating normally?
(D7900-D7905)
(D7919/D7921/D7923/D7925/D7927/D7929)

NO

Check defective parts and exchange the inferior products.

LC-32DH57E-BK/RU-BK/S-BK

4 – 30

Does a single or several 
vertical stripes appear 
on the LCD screen? 

Does a single or several 
horizontal stripes appear 
on the LCD screen?

Do luminescent or black 
dots appear on the 
screen?

 Is the on-screen image 
rippling or distorted?

Is there any portion 
which some screens 
were darkish or 
became whitish?

Replace the LCD panel.

The backlight func-
tions. Does not the 
image come out in the 
LCD screen 
(screen black)?

Does the entire LCD 
screen look whitish all 
over?

Does the QS drive func-
tion?

 Are the data bit drop-
out?
(No solution even when 
turning on and off the QS 
drive)

Is the gamma correc-
tion as specified?

Replace the LCD_CONT_UNIT.

LC-32DH57E-BK/RU-BK/S-BK

4 – 30

Does a single or several 
vertical stripes appear 
on the LCD screen? 

Does a single or several 
horizontal stripes appear 
on the LCD screen?

Do luminescent or black 
dots appear on the 
screen?

 Is the on-screen image 
rippling or distorted?

Is there any portion 
which some screens 
were darkish or 
became whitish?

Replace the LCD panel.

The backlight func-
tions. Does not the 
image come out in the 
LCD screen 
(screen black)?

Does the entire LCD 
screen look whitish all 
over?

Does the QS drive func-
tion?

 Are the data bit drop-
out?
(No solution even when 
turning on and off the QS 
drive)

Is the gamma correc-
tion as specified?

Replace the LCD_CONT_UNIT.

LC-32DH57E-BK/RU-BK/S-BK

4 – 30

Does a single or several 
vertical stripes appear 
on the LCD screen? 

Does a single or several 
horizontal stripes appear 
on the LCD screen?

Do luminescent or black 
dots appear on the 
screen?

 Is the on-screen image 
rippling or distorted?

Is there any portion 
which some screens 
were darkish or 
became whitish?

Replace the LCD panel.

The backlight func-
tions. Does not the 
image come out in the 
LCD screen 
(screen black)?

Does the entire LCD 
screen look whitish all 
over?

Does the QS drive func-
tion?

 Are the data bit drop-
out?
(No solution even when 
turning on and off the QS 
drive)

Is the gamma correc-
tion as specified?

Replace the LCD_CONT_UNIT.