Ethernet3 doesn’t work, drops ping packets
NOT OK
Change faulty connector J13
and Gigabyt Ethernet PHY
U19
Check termination resistance between Tx
and Rx in the connector J13. The
resistance should be 150Ohm +/-2%
Check voltage drop on D1, D3 pin#1
and ground. It should be in the range
from 0.3V to 0.4V measured in diode
mode (hold “positive” wire on the ground
and “COM” wire to D1 pin#1)
Change faulty diode array
D1, D3
NOT OK
O
K
Check ferrite beads FB2, FB13, FB14.
Ferrite beads resistance should be
less than 1 Ohm
Check Ethernet clock 25MHz on
R97 pins
O
K
Change faulty FB2,
FB13, FB14
Change frequency
generator U17
Change faulty Gigabit
Ethernet PHY U16
Check Ethernet clock
25MHz on crystal Y3 pins
NOT OK
Change faulty Gigabit
Ethernet PHY U16
NO 1.6V
O
K
Check 1.6-1.7V on C160 pins
O
K
NO 25MHz
NO 25MHz
NOT OK
The board is unrepairable
Problem still appears
Summary of Contents for RB800r2v5
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