IBM 6400 Maintenance Information Manual page 67

Operator Panel
Message
015
COMMUNICATIONS
CHECK
CHECK CABLE
016 INVALID
COMMAND
Table 4. Message List
Explanation
The line is not active
on a twinax interface.
The printer detects a
twinax protocol
communications error
and reports the error.
Corrective Action
1. Power off the printer. Disconnect the AC
power cord from the printer. Check the
twinax host data cable connection and
twinax I/O cable connection at the CT
board. Reseat the twinax host data cable
connection and the twinax I/O cable
connection at the CT board.
2. Disconnect the twinax auto-termination
cable from the printer. Test the cable for
the resistances shown on page 306. If
resistances are not correct, replace the
twinax auto-termination cable.
3. Connect the AC power cable to the
printer. Power on the printer. Send a print
job to the printer. Verify that all other
devices on the twinax line are working
properly. (Refer to line problem
determination procedures, as
recommended by the host system.) If the
message is gone, the host has
reestablished communication with the
printer. If all other twinax devices work
properly and the message still appears,
replace the coax/twinax expansion board.
Record the message and return it with
defective board.
1. Power off the printer. Disconnect the AC
power cord from the printer. Check the
twinax host data cable and twinax I/O
cable connection at the CT board. Reseat
the twinax host data cable connection
and the twinax I/O cable connection at
the CT board.
2. Disconnect the twinax auto-termination
cable from the printer. Test the cable for
the resistances shown on page 306. If
resistances are not correct, replace the
twinax auto-termination cable.
3. Connect the power cord to the printer.
Power on the printer. Send a print job to
the printer. If the message appears,
replace the twinax cable.
4. Send a print job to the printer. If the
message appears, go to
Communications Failures, page 131.
Message List
67