MiTAC 7521 PLUS/N Manuale Utente

127

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