It appears that badcaps is not as helpful as I thought.
ISTM that the symptoms point to a failure in the supply for the backlight. If you shine a torch at the display screen, do you see an image? If so, then it's a backlight fault.
The annotated photo clip and circuit diagram are my best guess as to the layout of the damaged area of the circuit. The IC appears to be a boost converter with either a 5-bit or 6-bit DAC for selecting 32 or 64 brightness levels.
I suspect that the backlight is shorted. This would have caused the failure of the 6.8uH coil, Schottky diode, and possibly the R01 resistor. With the display connected, measure the resistance between ground and the "display voltage" test point. A resistance of zero ohms would confirm that the display is shorted. Verify that the short goes away when the display is disconnected.
Verify that the V+ voltage is present on either side of the zero-ohm link and at inductor L.
Choose a high speed diode of at least 1A or better as a replacement for D.
Panasonic's ELL5PS6R8N coil, or equivalent, may be a suitable replacement for the 6.8uH coil. You will need to confirm the dimensions.
http://industrial.panasonic.com/lecs/ww ... 000CE7.pdfCode:
___ ___
V+ o--|___|---UUU--+----------------+
| |
0 ohm L --- C1 |
--- C|
| 6.8 uH C|
| C| D R01
=== | ___
GND +----->|---+---+--|___|--o
| | | display V
.----------------------------|---. | |
| .-----. boost | | | |
___ | | | converter | | --- ---
-|___|--|--| | | | --- --- C2, C3
___ | | | | | | |
-|___|--|--| | .-----. | | |___|
___ | | | | | | | |
-|___|--|--| | | | | | ===
___ | | DAC |----| PWM | | | GND
-|___|--|--| | | | | |
___ | | | '--.--' | |
-|___|--|--| | | ||-+ |
___ | | | | ||<- |
-|___|--|--| | '--------||-+ |
| | | | |
| '-----' | |
'--------------------------------'
|
|
===
GND
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HDDGURU FILES
Element on your photos is coil. Can you write model of motherboard? - there should be description directly on logic board.