LC-37XD1E (serv.man4). Troubleshooting Table - Sharp TV Service Manual (repair manual). Page 9

LC-37XD1E/RU

4 – 9

<0n input of the tuner (U/V)>                                                                      No picture on the display (1)

No picture appears on 
LCD during the tuner 
(U/V) reception. 

Checklist:

  1)  Is "INPUT SOURCE" button

on the remote control set up correctly ? ... See the operation manual and set "INPUT SOURCE" to "TV". 

  2)  Is MENU-Picture-Contrast/Brightness set to "MIN" ? ... Set it to an appropriate level. 
  3)  Is ANT-CABLE disconnected or connected improperly? ...Connect it correctly as per the operation manual.

YES

Is level of pins (9) and 
(8) of tuner (TU201) and 
pins (12)  and (2) of 
IC204 (MULTI) at H?   

NO

 These are communica-
tions lines for control 
(I2C). Follow the path and 
check whether  they are 
forced to 
L(PULL_DOWN).   

  

YES

  

Is the video signal (IF) 
sent from pin (11) of 
tuner (TU201 )?   

NO

 Check the tuner (TU201) 
and peripheral circuits.    

  

YES

  

Is the video signal 
CVBS sent to pin 
(AC23) of  lC3002 (V-
PRO.)?   

NO

Check CONNECTOR 
(P201 /SC2705) 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 (TA

± - 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.