Xerox WorkCentre Pro 423, Service Manual

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03/02 Level 2 Troubleshooting
WorkCentre Pro 423/428 2-77 CHAPTER 2 TROUBLESHOOTING
Type B
Type A
*3
Take action
based on
error code
Take action based
on session end
parameter (CSE,
CSA) and reason
(CDR, CDD,
RDBPN)
*1: The error codes depend on the
model and are subject to change. Refer
to the error descriptions in the service
manual.
*2: The voltage is 40 V +5% to -10%.
The TA-RA and TB-RB polarities are
negative on the T side and positive on
the R side.
The 8-pin connection block (RJ45) for
ISDN has the pins listed below. See
the figure for the pin order. The layout
of mounting screws in the connection
block is either A or B in the figure.
Pin 1: Not used
Pin 5: RB(+)
Pin 2: Not used Pin 6: TB(-)
Pin 3: TA(-) Pin 7: Not used
Pin 4: RA(+) Pin 8: Not used
*3: The polarity of voltage between L1
and L2 is inverted when the remote
party answers. A DSU or network fault
is also attributable to abnormal polarity
inversion.
*4: Replace the G4M PWB if no signals
(SQ, SF, and other) are recorded in the
network trace data.
· About terminator (Terminator: 100 ohms)
ISDN allows up to eight terminals to be
connected to a line. The terminals are
connected through a bus and the farthest
connection block or terminal requires a
terminator. If no terminator is attached to the
end of a bus connection line, the signal
waveform becomes unstable and causes a
Layer-1 problem. The error status varies.
Terminator attachment position: Between RA-
RB and TA-TB of the connection block farthest
from DSU
A TA or DSU may have a built-in terminator that
is switched ON and OFF. Check the settings of
all devices in a group to ensure that only one
terminator is ON.
No
Start Fax self-diag
Take action
based on
error code
Yes
Replace
ICM
PWB
Replace and
reconnect
cable
Yes
No
Network fault.
Request network
service agent
(NTT113 etc.) for
recovery
Wiring fault between
DSU and connection
block. Request home
wiring agent for
recovery.
DSU fault. Request
DSU service agent
for recovery.
RJ45 connection
block
Pin 1
Pin 8
Terminator (install only to the farthest collection block
from DSU)
4 RA
3 TA
2
1 RB 5
TB 6
7
8
1
2
3 TA
4 RA
8
7
TB 6
RB 5
Error code displayed?
Pin numbers (right) and
block inside (below)
(1) (3) (4)
(5)
(2)
(6)
DSU line (L1-L2)
voltage from 55 to 60
V during no call?