Samsung YP-U5, Руководство по обслуживанию

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Samsung Electronics 4-15
Troubleshooting
4-1-8 Poor PC Connection
Faulty connection to PC
Is the MP3 player
recognized when it is directly connected
to the PC USB port?
No
Execute recovery update and then
check it again.
Is a recovery
update possible?
No
Yes
Replace the board
(Detailed inspection is required.)
No
Check if C24,
C25, C36 or C40 are
short-circuited during the GND
short-circuit test.
1
When the MP3 player is
connected to the USB port, is the
voltage on IC7 Pin 5
approx. 5V?
Replace the faulty elements and
then check it again.
Replace IC7 and check the voltage
again.
No
Yes
Complete
(Faulty user hub or faulty
extension wire)
Yes
Replace the faulty elements or re-
solder and then check again.
Are R18 and R19 cold soldered?
Yes
Replace D1, D2 and D3 (remove
them if they are not replaced), and
then check again.
2
Is D3 element Pin 1 or Pin 2
short-circuited to GND?
Yes
Yes
No
No

Refer to wave pattern
image of Fig. 4-5.

Refer to wave pattern
image of Fig. 4-6.