LG KT-17LZ21, Service Manual

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1 No sound Defective Reset IC of IC604. 1) Check volume and speaker.
- Speaker Defective MSP3411 of IC601. - Sound comes out only when being inputted into Audio
- Earphone Defective B+(8V,5V) of IC603. L/R.
2) Check after replacing IC604.
3) Replace IC601.
4) Check and replace B+ of IC603.
2 Video color beat noise Earphone shield case being touched. Check the mould of shield and SJ209, Replace shield case.
Soldering IC301 and IC510. Re-soldering
1 No screen Input error of inverter connector 1) Bend the pin legs of P1 connector -> recheck them
2) Check and repair F804.
P704 connector 1) Check and fix P704 connector
being slipped out 2) Check and fix the components at P704 LCD module
and at main board.
3) Check Pin21.
Cracked components and Check and repair tuner board and main board
soldering at tuner board
2 Dark screen 1) Defective LCD lamp 1) Replace the inverter
2) Defective inverter 2) Replace the LCD lamp
3) Input error of inverter connector 2) Check the connector input.
TROUBLESHOOTING
1. General Features
2. PC Mode
No. Symptom Cause Check Point
No. Symptom Cause Check Point
Check Point
1 Screen noise Clock or phase being 1) Resettig is needed according to the video card of each
not able to be adjusted. PC.
2) Horizontal noise : adjust phase until no horizontal
noise occurres.
3) Vertical noise : adjust clock in menu until no vertical
noise occurres.
2 Screen position error Screen position error 1) Play the Auto Configure in Menu.
horizontally or vertically 2) Adjust horizontal and vertical position until the screen
displayes normally.
3 Color beat noise Soldering D-SUB Jack of JA202 Recheck adn repair JA202,IC202
and IC202.
3. TV and external input
No. Symptom Cause
4 . DVD Mode
1 When the KEY of DVD is not working: 1)Check the P801.
2 When the LOGO screen can’t display: 2)Check the 28PFFC cable.
3 When you can’t insert the DVD title: 3)Check the 8P power cable.
When you can’t see the screen:
4 If you can’t operate it after check the above status,
replace the DVD DECK.
No. Symptom Check Point