Panasonic KX-TD500 System Reference Manual page 1432

3.11 Conference trunk failure (Option)
Error Code
Possible cause of
the malfunction
Countermeasures
Note
09 xx
xx= 00 : for all optional conference trunks (01 to 64).
01 to 64 : for individual optional conference trunk 01 to 64.
1) Optional TSW Conference Expansion card on the TSW card is defective.
2) Malfunction of the TSW card.
Enter test command to check the
faulty trunk from the maintenance
terminal
Faulty
Replace the optional TSW
Conference Expansion Card
After turning the power switch on,
check the optional conference trunk
status
Faulty
Replace the TSW card
None
End
15-E-14
Pass
Enter INS command
from the maintenance
terminal
INS