Laptop User Manual

127
7521
7521
Plus / N N/B MAINTENANCE
Plus / N N/B MAINTENANCE
8.10 AUDIO FAILURE
No sound from speaker after audio driver is installed.
Check the following parts for cold solder or one of the following parts on the
motherboard may be defective,use an oscilloscope to check the following signal
or replace the parts one at a time and test after each replacement.
Parts
:
U5, C52
U6, C65
VR501
C81, C80
C71, C62
R52, R49
R45, R31
R64, R61
R34, R33
Charge BD
Signals:
AOUT_R
AOUT_L
ROUT+
ROUT-
LOUT+
LOUT-
SPK_OFF
1. If no sound cause of line
out, check the following
parts & signals:
2. If no sound cause of MIC,
check the following
parts & signals:
3. If no sound cause of
CD-ROM,check the
following parts & signals:
Parts
:
U5, C61
L506, L505
C75, J509
J4, L13, L10
R41, R42
C39, R50
D2, U4
Signals:
MIC1
Parts:
U5, C63
C73, C64
J512
Signals:
CDROM_LEFT
CDROM_RIGHT
CDROM_GND
AUDIO DRIVE FAILURE
1. Check if speaker cables are connected
properly.
2. Make sure all the drivers are installed
properly.
Test
OK?
1.Try another known good
speaker, CD-ROM.
2. Exchange another known
good charger board.
Test
OK?
Replace M/B or go
into board-level
Troubleshooting.
End.
Board-level
Troubleshooting for
audio test error.
YES
YES
NO
NO