Lan Failures - Samsung OfficeServ 12 Service Manual

3.7 LAN Failures

Failure
When the LAN does not work.
Troubleshooting
- Check the crystal signal(25 MHz)
pin27, pin28 of the U931
- Check 25 MHz output signal pin78 of
the U931
Is the clock normal?
Yes
Check the patterns from U931 to
RJ-45(P901)
Are the patterns normal?
Yes
- Replace U931
- Replace the base board
© SAMSUNG Electronics Co., Ltd.
END
No
Replace crystal(Y931)
No
Repair abnormal signals
15