LC-37XD1E (serv.man4). Troubleshooting Table - Sharp TV Service Manual (repair manual). Page 16

     LC-37XD1E/RU

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<When EXT4 is used for external input>                                                                        No picture on the display (6)

No EXT4 (15pin-D-SUB terminal) output of the external input sys-
tem.  

  

Checklist: 

  1)  Is "INPUT SOURCE" button 

on the remote control set up correctly ? ... See the operation manual and set  "INPUT SOURCE" to "EXT4".

  2)  Connect the included D-SUB-Adapter-Cable to the COMPONENT terminal of an external device. ...See the operation manual (use a commer-
cially available Component-Cable to connect to the external device).
  3)  Is ANT-CABLE disconnected or connected improperly ? ... Connect it correctly as per the operation manual

Is "EXT4" selected 

with

button on the 

remote control    

NO

Select "EXT4" with   

button  on the 

remote control.     

YES

Is D-SUB-COMPONENT 
signal (APC_R/G/B) sent 
to pins (1),(2) and (3) of 
EXT4-TERMINAL 
(SC2303) ?   

NO

Check D-SUB-adaptor 
and external connection.     

YES

Is D-SUB-COMPONENT 
signal  (APC-R/G/B) sent 
to pins (AA17),(AB17) 
and (Y17) of  IC3002 (V-
PRO.) ?    

NO

Check EXT4-TERMI-
NAL and  peripheral cir-
cuits.     

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

± - 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 HAR-
NESS WIRE (PL).

YES

 Replace LCD-CONT-UNIT.