50PK550-UD, 50PK550-UE (CHASSIS:PU01A) - LG TV Service Manual (repair manual). Page 10

PC (for communication through RS-232C)     UART Baud rate
: 115200 bps
Command : aa 00 00 (Start factory mode)
Command : ad 00 10 (working Auto ADC)
Command : aa 00 90 (End of Auto ADC Process)

After  enter  Service  Mode  by  pushing  “ADJ”  key,  execute
“ADC Adjust” by pushing “

G

” key at “0. ADC CALIBRATION”. 

(1) We  confirm  whether  “0xBF(480i)/0xC8(1080i)”  address  of

EEPROM “0xA2” is “0xAA” or not. 

(2) If  “0xBF(480i)/0xC8(1080i)”  address  of  EEPROM  “0xA2”

isn’t “0xAA”, we adjust once more

(3) We can confirm the ADC values from “0xB9 ~ 0xBE(480i) /

0xC2 ~ (1080i)” addresses in a page “0xA2”

* Manual  ADC  Confirmation  using  Service  Remocon.  After

enter Service Mode by pushing “INSTART” key,

* Caution : Each  PCB  assembly  must  be  checked  by  check  JIG

set.(Because power PCB Assembly damages to PDP
Module, especially be careful)

* Caution: Set up “RF mode(noise)” before voltage adjustment.

(Va, Vs voltage adjustment)

(1) Test equipment : D.M.M 1EA
(2) Connection Diagram for Measuring : refer to fig.1

(fig.1 : Power PCB Assy Voltage adjustment)

(1) Vs adjustment (refer fig.1)

1) Connect  +  terminal  of  D.M.M.  to  Vs  pin  of

P812(42”:P811),  connect  -terminal  to  GND  pin  of
P812(42”:P811)

2) After  turning  VR901,  voltage  of  D.M.M  adjustment  as

same  as  Vs  voltage  which  on  label  of  panel  left/top    (
deviation ; ±0.5V)

(2) Va adjustment (refer fig.1)                                               

1) After receiving 100% Full White Pattern, HEAT RUN.
2) Connect  +  terminal  of  D.M.M.  to  Va  pin  of

P812(42”:P811),  connect  -terminal  to  GND  pin  of
P811(42”:P812).

3) After  turning  VR502,voltage  of  D.M.M  adjustment  as

same  as  Va  voltage  which  on  label  of  panel  left/top
(deviation; ±0.5V)

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<XPOWER4 50R1 PSU>