Fujitsu AUXB04GALH Service Manual page 159

Signal Amplifier (UTY-VSGXZ1 )
Trouble shooting 81
Error Contents :
Communication Error B
Details :
Condition of occurrence : Communication error between CPU and Network Driver IC (CH_B side).
Release condition : Communication is normal between CPU and Network Driver IC (CH_B side).
Network Driver IC operation is normal.
Cause 1 : External noise
Upon pressing RESET button (SW7) or turning on power,
proceed as follows.
(1) If error did not appear, it is not a defect of PCB. Remove the
surrounding noise source.
(2) If error occurs again, check followings other than removing
surrounding noise source.
Symptom :
Error display [ D9 (Flashing or Lighting) ]
No operation.
Network Driver IC is defective.
OK
Cause 2 :Signal Amplifier is defective.
Replace Signal Amplifier.
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