19LV2500-UG (CHASSIS:LA01R) - LG TV Service Manual (repair manual). Page 10

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This spec. sheet applies to LA01R Chassis applied LCD TV
all models manufactured in TV factory. 

2.1   Because this is not a hot chassis, it is not necessary

to use an isolation transformer. However, the use of
isolation transformer will help protect test instrument.  

2.2   Adjustment must be done in the correct order.  
2.3  The adjustment must be performed in the

circumstance of  25±5°C of temperature and 65±10%
of relative humidity   

2.4   The input voltage of the receiver must keep

100~240V~, 50/60Hz.  

2.5 At first Worker must turn on the SET by using Power

Only key.  

2.5    The receiver must be operated for about 5 minutes

prior to the adjustment when module is in the
circumstance of over 15. 

In case of keeping module is in the circumstance of
0°C, it should be placed in the circumstance of above
15°C for 2 hours  

In case of keeping module is in the circumstance of
below -20°C, it should be placed in the circumstance
of above 15°C for  3 hours. 

• Caution 
When a still image is displayed for 20 minutes or longer
(especially where W/B scale is strong.  Digital pattern 13ch
and/or Cross hatch pattern 09ch), there can some
afterimage in the black level area. 

(1) Adjust 1080p/480i Component(ADC)
(2) EDID/DDC download  

• Remark 

- Above adjustment items can be also performed in Final

Assembly if needed. Adjustment items in both PCBA and
final assembly stages can be checked by using the
INSTART Menu  1.ADJUST CHECK. 

(1) White Balance adjustment 
(2) RS-232C functionality check 
(3) Factory Option setting per destination 
(4) Shipment mode setting (IN-STOP) 

(1) Ship-out mode  
(2) Service Option Default  
(3) USB Download(S/W Update, Option, Service only)  
(4) ISP Download (Optional) 

4.1.1. Overview 
• ADC adjustment is needed to find the optimum black level

and gain in Analog-to-Digital device and to compensate RGB
deviation. 

4.1.2. Equipment & Condition 
1) Jig (RS-232C protocol) 

• Required equipment : Adjustment R/C 

*Enter Service Mode by pushing “ADJ” key, 

G

” key at “6. ADC

Calibration” 

4.1.3. Adjustment 

4.1.3.1 Adjustment method  
• Using RS-232, adjust items listed in 3.1 in the other

shown in “4.1.3.3” 

4.1.3.2 Adj. protocol  

Ref.) ADC Adj. RS232C Protocol_Ver1.0 

4.1.3.3. Adj. order 
• aa 00 00  [Enter ADC adj. mode] 
• xb 00 40  [Change input source to Component1(1080i)] 
• ad 00 10  [Adjust 480i Comp1] 
• xb 00 60  [Change input source to RGB(1024*768)] 
• ad 00 10  [Adjust 1024*768 RGB] 
• ad 00 90  End adj. 

Ref) ADC adj. RS232C Protocol_Ver1.0 

Protocol

 Command 

Set ACK 

Enter adj. mode 

aa 00 00 

a 00 OK00x 

Source change 

xb 00 40 
xb 00 60  

b 00 OK40x (Adjust 480i /1080p Comp1 ) 
b 00 OK60x (Adjust 1920*1080 RGB) 

Begin adj. 

ad 00 10 

 

Return adj. result 

 

OKx (Case of Success) 
NGx (Case of Fail) 

Read adj. data 

(main) 
ad 00 20  
 
(sub ) 
ad 00 21 

(main) 
000000000000000000000000007c007b006dx 
 
(Sub) 
000000070000000000000000007c00830077x 

Confirm adj. 

ad 00 99 

NG 03 00x (Fai l)
NG 03 01x (Fai l)
NG 03 02x (Fai l)
OK 03 03x (Success) 

End adj. 

aa 00 90 

a 00 OK90x