MiTAC 8050 服务手册

115

Test 

OK?

1. Check if  speaker cables are connected

properly.

2. Make sure all the drivers are installed  

properly.

Try another known good speaker,
CD-ROM.

Re-test 

OK?

Board-level

Troubleshooting

Replace

Motherboard

Yes

Correct it.

Yes

No

No

U18
U17
U524
U726
U715
U712
U19
U725
J3
J7
J705
J719
L741

ROUT+
ROUT-
SBSPKR
CARDSPK#
PC_BEEP
AVDD
ACRST#
ACSDOUT
ACSDIN0
ACBITCLK
14M_CODEC
MIC_VREF
2464_VREF

Replace the
faulty parts.

Check following parts and signals:

D715
Q711
Q713
Q23
D17
D19
D22
U18

AMP_LEFT
AMP_RIGHT 
SUB_LEFT
SUB_RIGHT
AMP_SHUTDOWN
ROUT+
ROUT-
LOUT+
LOUT-