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25 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.
Thank you
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2 Comments
I did a swap from the display assembly.
Where is fuse located in the logic board ?
is this fuse for internal monitor only ? because external working fine
I did visual check of TDMS pins
on the board- looks okay.
by Vitali
If you still have the other system handy try plugging it in directly on the logic board (just be careful as the cord is very short and easy to damage). If not, I would first swap out the cable (more likely worn out).
by Dan