Blank Screen, but external works fine
iMac G4 20 inch model has a blank screen. But working fine when connect to the external monitor over miniVGA.
Screen backlight is okay, brightness is changing, but no any sign of picture.
I did a monitor swap from the same model with the same model number, but it is still blank.
Looks like video chip is okay and provide signal to the external monitor but no signal to the TDMS on internal screen.
Please help me.
Is this a good question?