Acer AT4220A Service Manual page 70

VGA/DVI No Sound
PC/DVI can Display ?
Mute turn off
Volume set to 50
Audio Line in
Cable Plug IN?
Sound Normal ? Sound Normal ?
63
M
END
no
Check Video cable or PC or
Replacement VGA/DVI cable
Check Line in cable or
no
Replacement Line in Cable
no
Replacement Main/B Replacement Main/B
Chapter 3