Panasonic KX-TD500 System Reference Manual page 1267

DATA ERROR No.
030 A checksum error has been detected.
031 Improper data is received.
040 Execution is impossible during off-line.
041 Impossible change such as
[INS] → [INS],
is attempted.
042 Some required items are omitted.
043 The number of equipment you attempt to
assign is over the limit.
045 Slot number you specified is not valid. (DTM,
LBT command)
046 Card type you specified is not valid. (DTM,
LBT command)
047 The status of the card you specified is not
valid. (DTM, LBT command)
048 No DTMF Generator/Receiver is installed on
the card you specified.
049 You specified the DTMF Generator/Receiver
of different cards.
Probable Cause
[OUS] → [OUS]
11-D-7
Countermeasure
Communication line is defective, or backup
data is destroyed.
Communication link is defective, or backup
data is destroyed.
Execute during on-line.
Impossible.
Enter the required items.
Assign the equipment within the limit of
number.
Specify the slot in which T-1/E-1 card is
installed.
Specify the T-1/E-1 card.
Change the staus to valid one.
Install the optional DTMF Generator/Receiver
card.
Specify the DTMF Generator/Receiver of the
same card.