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LC-42XD1EA/RUA

4 – 17

<When EXT5 is used for external input>                                  No picture on the display (7)

             
No EXT5 (HDMI) output of the external input system.

             
Checklist:

1) Is “INPUT SOURCE” button

on the remote control set up correctly? ... See the operation manual and set “INPUT SOURCE” to “EXT5”.

2) Have you checked the type video signal sent from HDMI-connected external device? ... Confirm the type (it should “RGB”, “YCbCr 4:4:4” or 

“YCbCr 4:2:2”).

3) Have you checked the type of Color matrix sent from HDMI-connected external device? ... Confirm the type (it should be “ITU601” or “ITU709”.)
4) Is ANT-CABLE disconnected or connected improperly? ... Connect it correctly as per the operation manual

             

Is “EXT5” selected with

button on the remote control?   

NO

Select “EXT5” with 

button on the remote control.     

YES

Is the type of video signal (Signal Type) from HDMI- connected 
external device set?   
    

NO

From MENU-Connections-HDMI setup-EXT5-Signal type, select a 
signal type
 (“RGB”, “YCbCr 4:4:4” or “YCbCr 4:2:2”)     

YES

Is the type of color signal (Color matrix) from HDMI -connected 
external device set?    

NO

From MENU-Connections-HDMI setup-EXT5-Color Matrix, select a 
color signal type (“ITU601” or “ITU709”)     

YES

Is TMDS signal (RX*

±signal) sent to pins          (1) - (12) of 

EXT5 (HDMI) terminal (SC1901)?    

NO

Is I2C signal (SDA/SCL signal) sent to pins (16) and (15) of EXT5 
(HDMI) terminal? Check external connection and peripheral circuits.   

YES

Is 8bit-DIGITAL signal (HDMI- R/G/B) sent from pins (110)- 
(144) of IC1905 (HDMI-RECEIVER)?    

NO

Check power supply (3.3/1.8V) pins (99) and (74) of IC1905,
SDA/SCL signal pins (29) and (30), and peripheral circuits.    

YES

Is 8bit-DIGITAL signal (HDMI- R/G/B) sent to pins (B10) - 
(D15) of IC3002 (V-PRO.)?    

NO

Check SDA3/SCL3 signal pins (27) and (28), interface between 
IC1905 and lC3002, and peripheral circuits.    

YES

Is LVDS video signal (TA1

± - TD1±) sent to pins (AB8)/(AC8) - (AB3)/(AC3) of IC3002 (V-PRO.), and is 

CLK signal (CK1

±) sent to pins (AB5)/(AC5)?

Is LVDS video signal (TA2

± - TD2±) sent to pins (AC2)/(AC1) - (V2)/(V1) of IC3002 (V-PRO.), and is 

CLK signal (CK2

±) sent to pins (Y2)/(Y1)?

NO

Check pins (G14)/(U10) of 
BU3.3V line of IC3002 (V-
PRO.), pins (G10)/(N17) of 
BU2.5V line, pins (U16)/
(G12) of BU1.8V line and 
peripheral circuits.

YES

Is LVDS video signal (TA1

± - TD1±) sent to pins (3)/(2) -(12)/(11) of CONNECTOR CN1 of LCD-CONT-

UNIT, and is CLK signal (CK1

±) sent to pins (10)/(9)?

Is LVDS video signal (TA2

± - TD2±) sent to pins (17)/(16) -(26)/(25) of CONNECTOR CN1 of LCD-

CONT-UNIT, and is CLK signal (CK2

±) sent to pins (24)/(23)?

NO

Check CONNECTOR 
(SC2302, CN1) and HAR-
NESS WIRE (LV).

YES

Is power (+12V) supplied to pins (1) - (5) of CONNECTOR CN2 in LCD-CONT-UNIT? 

NO

Check CONNECTOR 
(CN2,P707) and HARNESS 
WIRE (PL).

YES

Replace LCD-CONT-UNIT.

LC-42XD1EA/RUA

4 – 18

<When EXT6 is used for external input>                                No picture on the display (8)

             
No EXT6 (HDMI) output of the external input system.

             
Checklist:

1) Is “INPUT SOURCE” button

on the remote control set up correctly? ... See the operation manual and set “INPUT SOURCE” to “EXT6”.

2) Have you checked the type video signal sent from HDMI-connected external device? ... Confirm the type (it should “RGB”, “YCbCr 4:4:4” or 

“YCbCr 4:2:2”).

3) Have you checked the type of Color matrix sent from HDMI-connected external device? ... Confirm the type (it should be “ITU601” or “ITU709”.)
4) Is ANT-CABLE disconnected or connected improperly? ... Connect it correctly as per the operation manual.

             

Is “EXT6” selected with

button on the remote control?   

NO

Select “EXT6” with   

button on the remote control.     

YES

Is the type of video signal (Signal Type) from HDMI- connected 
external device set?   
    

NO

From MENU-Connections-HDMI setup-EXT6-Signal type, select a 
signal type (“RGB”, “YCbCr 4:4:4” or “YCbCr 4:2:2”)     

YES

Is the type of color signal (Color matrix) from HDMI -connected 
external device set?    

NO

From MENU-Connections-HDMI setup-EXT6-Color Matrix, select a 
color signal type (“ITU601” or “ITU709”)     

YES

Is TMDS signal (RX*

±signal) sent to pins (1) - (12) of EXT6 

(HDMI) terminal (SC1902)?    

NO

Is I2C signal (SDA/SCL signal) sent to pins (16) and (15) of EXT6 
(HDMI) terminal? Check external connection and peripheral cir-
cuits.   

YES

Is 8bit-DIGITAL signal (HDMI- R/G/B) sent from pins (110)- 
(144) of IC1905 (HDMI-RECEIVER)?    

NO

Check power supply (3.3/1.8V) pins (99) and (74) of IC1905,
SDA/SCL signal pins (29) and (30), and peripheral circuits.    

YES

Is 8bit-DIGITAL signal (HDMI- R/G/B) sent to pins (B10) - (D15) 
of IC3002 (V-PRO.)?    

NO

Check SDA3/SCL3 signal pins (27) and (28), interface between 
IC1905 and lC3002, and peripheral circuits.    

YES

Is LVDS video signal (TA1

± - TD1±) sent to pins (AB8)/(AC8) -

(AB3)/(AC3) of IC3002 (V-PRO.), and is CLK signal (CK1

±) 

sent to pins (AB5)/(AC5)?
Is LVDS video signal (TA2

± - TD2±) sent to pins (AC2)/(AC1) - 

(V2)/(V1) of IC3002 (V-PRO.), and is CLK signal (CK2

±) sent to 

pins (Y2)/(Y1)?

NO

Check pins (G14)/(U10) of BU3.3V line of IC3002 (V-PRO.), pins 
(G10)/(N17) of BU2.5V line, pins (U16)/(G12) of BU1.8V line and 
peripheral circuits.

YES

Is LVDS video signal (TA1

± - TD1±) sent to pins (3)/(2) -(12)/(11) of CONNECTOR CN1 of LCD-

CONT-UNIT, and is CLK signal (CK1

±) sent to pins (10)/(9)?

Is LVDS video signal (TA2

± - TD2±) sent to pins (17)/(16) -(26)/(25) of CONNECTOR CN1 of LCD-

CONT-UNIT, and is CLK signal (CK2

±) sent to pins (24)/(23)?

NO

Check CONNECTOR 
(SC2302, CN1) and 
HARNESS WIRE (LV).

YES

Is power (+12V) supplied to pins (1) - (5) of CONNECTOR CN2 in LCD-CONT-UNIT? 

NO

Check CONNECTOR (CN2, 
P707) and HARNESS WIRE 
(PL).

YES

Replace LCD-CONT-UNIT.

LC-42XD1EA/RUA

4 – 19

                         
Note: The SD signal (576i 480i) alone passes through the FRC circuit. (The HD signal does not go through.)

                         

                        

                       

Does the image appear with the HD sig-
nal, but not with the SD signal?

Does anything unusual (which or black-
ish screen, block noise, for example) 
appear on the screen?      

Does the image look unusual with the 
power switch turned on?    

YES

YES

YES

Is the power supplied to IC3301 (FRC)?
Is there the FRC-IN signal input at pins 
(142) and (13) of IC3301? 
Check the soldering condition. 

Is there the specified RESET-A signal 
input at pin (39) of IC3301 (FRC)? 
(60 ms delay design)     

Check the connection between pin 
(R22) of IC3002 (V-PRO.) and pin 
(142) of IC3301 (FRC) as well as that 
between pin (N20) of IC3302 and pin 
(13) of IC3301    

YES

NO

Replace IC3301 (FRC).

Check “RESET-A” signal pin (34) of 
IC1710 (FPGA).     

                      
Do all the fluorescent tubes light up?

NO

Check the individual fluorescent 
tubes for light-up failure.

YES

Replace any defective fluorescent 
tubes with new ones.

YES

Is the power supplied to CN7501 on 
the inverter unit? 

NO

Check the connection between power 
unit and inverter unit.

YES

Is the fuse (F7501 or F7502) in the 
inverter unit circuit functioning?

NO

Replace the blown-out fuse (F7501 or 
F7502) on the inverter unit. Turn on 
the power again. 
If the fuse gets blown out again, 
check the short-circuited spot.

YES

Check the transformer (T7501-T7511, 
T7601-T7606) and their peripheral cir-
cuits as well as IC7501 and their 
peripheral circuits. 

YES

Is the VCC power supplied to the 
control IC (IC7501) on the inverter 
unit?

NO

Check the circuit connected with the 
VCC terminal on the inverter control 
IC (IC7501).

YES

Has each control signal come to 
CN7502(LB)? 
(OFL,OSC,STB)

NO

Have the OFL,OSC and STB signal 
come to P1701(LB) in the MAIN sub-
strate? 

NO

 Check pins (19),(17) and (89) of 
IC1710 (main PWB).

YES

Is the specified control signal input-
ted at IC7501 (INV-CTL) on the 
inverter unit.

NO

Check the line between CN7502 and 
IC7501. 

YES

Are the Q7501 and Q7502 transis-
ters at the primary side of T7501 
functioning?

NO

Check the power line of IC7501, its 
peripheral circuits or replace IC7501.    

YES

Is the secondary circuit of T7501 
functioning.

NO

Replace T7501 or the T*** trans-
former for the fluorescent tubes, or 
check their peripheral circuits.    

LC-42XD1EA/RUA

4 – 20

Does a single or several verti-
cal stripes appear on the LCD 
screen? 

Does a single or several hori-
zontal stripes appear on the 
LCD screen?

Do luminescent or black dots 
appear on the screen?

 Is the on-screen image rip-
pling or distorted?

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 control unit.