Usb Port Test Error - MiTAC 8050QMA Service Manual

8.9 USB Test Error-1
An error occurs when a USB I/O device is installed.
USB Test Error
Check if the USB device is installed
properly.
Yes
Test
OK?
No
Replace another known good USB
device.
Yes
Re-test
OK?
No
80 50QMA N/B Maintenance
80 50QMA N/B Maintenance
Board-level
Troubleshooting
Correct it.
Replace
Motherboard
Correct it.
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.
Parts:
U709
U501
U503
J701
J706
L5
L6
L10
L13
F503
F504
C2
C501
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
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