Text preview for : MP015ATS.pdf part of LG MP015ATS LG TV RT-44-49-54NA11T MP015ATS.pdf



Back to : MP015ATS.pdf | Home

Trouble Shooting
1. NO PICTURE ( SOUND OK )



CVBS Signal ?
Check MAIN1 Q101(E) Waveform. (2Vpp)




YES NO



NO
Check around
Waveform of AV Board IC202 #63 ? Check Tuner(TU101) VIDEO output
IC202


YES


NO
Waveform of AV Board Q505(E) ? Check around IC202


YES


Waveform of VIDEO Board NO
IC501 #72 ? Check IC501


YES


NO
Waveform of VIDEO Board Check around IC501 #31~#50
IC501 #31~#50? Output circuit.


YES


Waveform of VIDEO Board NO Check aroundIC706
IC706 #84,87,90 ?


YES


NO
Waveform of VIDEO Board
Check around IC702
IC702 #26,28,30 ?

YES


NO
Waveform of
Check IC901 R.G.B
CPT SOKET CATHODE(RK/GK/BK) ?



- 18 -
2. NO SOUND (PICTURE OK)

< RF >


Waveform of AV Board IC205 Checkarround Waveform of
NO NO Check
#47,48,50,51,53,54,56,57 each Jack MAIN1 Q103
at each Mode ? Q104 ( SIF ) ? TU101



YES YES


Waveform of Check
YES NO
AV Board IC205 around
#67 ? IC205




Waveform of AV Board NO
IC205 #25,27,28 ? Check around IC205




YES




Waveform of MAIN1 NO Check around AV
IC601 #7 #11 ? Board Q215,216,217




YES




Waveform of MAIN1 NO Check around
IC601? IC601,602




- 19 -
3. NO PIP


Waveform of PIP
Waveform of AV Board Waveform of MAIN1 Board IC502
IC202 #8,15,22,35 ? Q110(E) ? #1,2,3,7,9 ?


NO
Check JA202
YES YES


NO
Waveform of Video Board Check Video Board
IC202 #44 ? Q203,IC202
Check
YES NO ScartJack
JA204
YES



NO
Waveform of Video Board Check P212B
IC502 #72 ?




YES



Waveform of Video Board NO
IC502 #31~#50 ? Check around IC502
(R,G,B, FB)




YES




Waveform of Video NO
Check PIP Board
IC706 #51~#73 ?
IC706
( Y,U,V)




- 20 -
4. NO Teletext (Picture OK)



Waveform of MAIN1
IC501 #4 ?

YES

NO CheckMicom IC001
Micom Board Ic001 #21 ?
#57~60

YES

Check OPTION3 TEXT Code
(SVC MODE)




5. NO OSD (ON SCREEN DISPLAY)



Waveform of Micom Board IC001#29,#30 ? Horizontal, Vertical Fly Back Input


NO


YES
Check DEF. Board.
CheckMicom Board Q001,002



NO
Waveform of Micom Board IC001 #57,58,59, Check around IC001
60 ?

YES


NO
Waveform of Video Board Ic702
#83,84,85,86 ? (R,G,B,FB) Check around IC702




- 21 -
6. NO POWER ON




Check input voltage of NO
Check SMPS Board
IC001#6,8,22,40,56,73,75,92


YES


Check IC001 #52,53 NO
Replace X001
(OSC)


YES

NO
Check IC001 #11,12 (SCL,SDA) Replace Q003, Q004



YES


LOW
Check IC001 #44 (ABN) CheckAbnormnalCircuit



HIGH


Check IC001 #34 ( IR ), NO
Check P004A connector
#31~38 (Key In)




- 22 -
7. NO VFD OPERATION (Option)




Check AV Board IC205 #5 NO
Sound signal. Check IC205sound output




YES

NO
Check IC205 #3 output Check around IC205




YES

NO
Check IC001 #45,46 Check Q008, 007




YES


NO
Check IC001 #47,48,49 Check Q011, Q012




- 23 -
8.NO RASTER
Check +B voltage
115V or not


OK 0V


No
Is the voltage Open
at Pin 76,69 of IC501 5V ? Check F801


Yes Check 5V,9V, OK Check / Replace
12V lines F801,D815
Does the square IC801
waveform from Pin 17 Yes Check the voltage
of IC702 appear? of C812(+) 0V
No
Check / Replace Check IIC bus lines
IC702 Yes (SDA,SCL)
Check / Replace
D815
Is the waveform at
collector Q402 normal?
Check the voltage Lower than 6V
No
at pin 4 of IC801
Check / Replace
Q402,T401 Yes Check / Replace
6~8V D805,Q801
ZD801


Is the waveform at
collector Q403 normal? Check/Replace IC887,IC871
Check the 2nd voltage are
No
short or not


Check / Replace
Q403
Yes




Check / Replace
T401




- 24 -
9. INCORRECT CONVERGENCE


Does the static convergence
correct?


NO YES



Check the input
vlotage Re-adjust static convergence
at P201 by remote controller

YES NO Not controlled Controlled


Check pulse pin125 Check voltage on the Are there pulse signal
of IC2051(4Mhz) SMPS PCB at pin121 of IC2051 OK




NO YES
YES NO
Are there V,H pulse Check / Replace
Check/Replace Check V,H at
at Pin 3,4 of P404 Q2201
IC2051 Pin 2,4 of P404




YES NO NO YES




Check / Replace Check H,V Check V,H signal Check /Replace
IC2002 on the DEF PCB on the DEF PCB IC2051




- 25 -