Lcd Led Plasma T.V Repair Books
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AELEXIAN EMPIRE :: Analog and Mixed Signal Device Repair (Electronics Technician Board) :: LCD - LED TV REPAIR
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Lcd Led Plasma T.V Repair Books
by DJFEL Thu Oct 29, 2015 10:03 pm
Lcd Led Plasma T.V Repair Books
LCD issues can probably tell you which part is faulty. So lets go to the symptons:
1. LCD lights up for less then 5 seconds, then it goes blank (check if you can see picture):
- it could be dead capacitors on the inverter low voltage line (high probability)
- it could be a faulty inverter (low probability)
- it could be a faulty cold cathod flourescent tube inside LCD module - CCFL (very rare)
2. LCD power LED blinks but monitor does not light up:
- it could be dead capacitors on the 5V logic line to the main board (high probability)
- it could be faulty main board (very rare)
- it could be a dead LCD module (very rare)
3. LCD turns on, the picture is fuzzy:
- it could be faulty capacitors on SMPS (high probability)
- it could be defective main board (low probability)
- it could be defective LCD module (very rare)
- flex cables in the LCD module have a weak connection (very rare)
- LVDS cable is defective (very rare)
4. LCD turns on, backlight turns on, but gray or white screen appears:
- LCD module is defective (high probability)
- poor connection of LVDS cable (very rare)
5. LCD emmits strange buzz sounds:
- dead capacitors or inverters (high probability)
- faulty CCFL (low probability)
6. LCD works ok, but sometimes it seems like that buttons are pressed for no reason (OSD menu appears):
- faulty buttons (high probability)
- faulty main board (very rare)
7. LCD appears to be completly dead (no LED signal light)
- it could be faulty capacitors on the 5V logic line (high probability)
- it could be the fuse on SMPS (rare and probably for a reason)
- it could be faulty main board (very rare)
These simptoms can tell you very much of your fault. Now lets beggin with our dissasembly... I had a 17" Samsung monitor, with an issue number 1.
LCDs are encased in plastic housing which is hold together with few screws and a click sistem. This is probably the tricky part of disassembly. When you remove the housing, carefully remove the LCD module. But before you proceed, unplug the CCFL cables from the SMPS board that hide behind a metal shield.
LCD issues can probably tell you which part is faulty. So lets go to the symptons:
1. LCD lights up for less then 5 seconds, then it goes blank (check if you can see picture):
- it could be dead capacitors on the inverter low voltage line (high probability)
- it could be a faulty inverter (low probability)
- it could be a faulty cold cathod flourescent tube inside LCD module - CCFL (very rare)
2. LCD power LED blinks but monitor does not light up:
- it could be dead capacitors on the 5V logic line to the main board (high probability)
- it could be faulty main board (very rare)
- it could be a dead LCD module (very rare)
3. LCD turns on, the picture is fuzzy:
- it could be faulty capacitors on SMPS (high probability)
- it could be defective main board (low probability)
- it could be defective LCD module (very rare)
- flex cables in the LCD module have a weak connection (very rare)
- LVDS cable is defective (very rare)
4. LCD turns on, backlight turns on, but gray or white screen appears:
- LCD module is defective (high probability)
- poor connection of LVDS cable (very rare)
5. LCD emmits strange buzz sounds:
- dead capacitors or inverters (high probability)
- faulty CCFL (low probability)
6. LCD works ok, but sometimes it seems like that buttons are pressed for no reason (OSD menu appears):
- faulty buttons (high probability)
- faulty main board (very rare)
7. LCD appears to be completly dead (no LED signal light)
- it could be faulty capacitors on the 5V logic line (high probability)
- it could be the fuse on SMPS (rare and probably for a reason)
- it could be faulty main board (very rare)
These simptoms can tell you very much of your fault. Now lets beggin with our dissasembly... I had a 17" Samsung monitor, with an issue number 1.
LCDs are encased in plastic housing which is hold together with few screws and a click sistem. This is probably the tricky part of disassembly. When you remove the housing, carefully remove the LCD module. But before you proceed, unplug the CCFL cables from the SMPS board that hide behind a metal shield.
DJFEL- 24V BATTERY
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Age : 42
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Electro- 24V BATTERY
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Age : 35
Location : Calinan Davao City
AELEXIAN EMPIRE :: Analog and Mixed Signal Device Repair (Electronics Technician Board) :: LCD - LED TV REPAIR
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