I had the issue with my laptop and the screen was black. The first thing i did was connected it to an external screen and I did get a picture on the screen. When I did a search on my problem it seemed to point to the inverter. Because i bypassed the laptop screen when going to the external it also bypassed the inverter. But my problem turned out not to be the inverter but the LCD cable that connects to the inverter.
I found this on the net
The defective LCD Backlight inverter will cause the following symptoms:
•No Display, but the power indicate light will stay on green or blue.
•Screen will flash on and off and the power indicate light will stay on green or blue.
My Toshiba p205 s6347laptop was taken apart and cleaned and now won't start. When I press the power button the power light comes on blue for a second then the hdd light flashes once and the power flashes amber twice, blue once,then repeats the pattern (hdd light only the one time). The screeen stays black, no beeps but you can hear the fan and a couple clicks. If a cd is in the drive it will spin but not boot. I tried the generic reset and then when I turned it on the power light stayed blue but it wont turn on. Turn it off and back on and it's back to the flashing. HELP! Is it a goner?