LL-T1512W
4 – 1
CHAPTER 4. TROUBLESHOOTING
No power supply
Does LED turns on in green
when power switch is turned
on?
No
No
No
No
No
No
LED turns on in red?
Yes
Yes
Yes
Yes
Yes
Yes
Yes
* Check LED for breakage.
* Check cable for disconnection.
Replace any unit (main PWB, SW PWB, cable)
which shows any defect, with a new one.
1) PC is turned off?
2) RGB cable is disconnected?
3) Synchronizing signal is output from RGB
cable?
Check whether the unit is in power save
mode (synchronizing signal is not input.).
Synchronizing signal is input to main PWB?
Replace RGB cable
with a new one.
LED turns on in orange?
Check power input system.
1) AC adapter
* Normal?
* Connected properly?
2) Blown out fuse (F1, F2) ?
3) Each signal of 5V, D3, 3V, PVDD,
AVDD1.8V is output ?
4) LED
* Check LED for breakage.
* Check the path between CN10 and
IC22.
* Check the cable for disconnection.
Replace any defective unit.
[ 1) Adapter, 2) A Main PWB, 3) Switch
PWB, ] with a new one.
Backlight turns ON?
Check for RGB cable input
signal.
Replace RGB cable.
Normal
Normal
Normal
Defective
Defective
* Check inverter block of main PWB.
Note: Use caution when checking output
side because it has a high voltage.
Replace LCD module lamp with
a new one.
Replace main PWB
unit with a new one.
A
Check each signal of
BL_ON,+12V,BRI(150Hz,
Duty 15~65%)
