MiTAC 8050QMA - Manual (Page 128)

127
80 80 50QMA 50QMA N/B Maintenance N/B Maintenance
8.9 USB Test Error-1
An error occurs when a USB I/O device is installed.
Re-test
OK?
Test
OK?
USB Test Error
Check if the USB device is installed
properly.
No
Yes
No
Yes
Check the following parts for cold solder or one of the following
parts on the mother-board may be defective, use an oscilloscope
to check the following signal or replace the parts one at a time
and test after each replacement.
Replace another known good USB
device.
Board-level
Troubleshooting
Correct it.
Correct it.
Replace
Motherboard
Signals:
USB_OC0#
USB_OC1#
USBP[0..3]+
USBP[0..3]-
+VCC_USB_0
+VCC_USB_1
+VCC_USB_2
+VCC_USB_3
+5V
SW_VDD3
Parts:
U709
U501
U503
J701
J706
L5
L6
L10
L13
F503
F504
C2
C501
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