IBM Aptiva 2170 Hardware Maintenance Service Manual page 190

CIS-Non Voice
CIS-Voice
CIS Factory-Installed Modem Card Connector Functions
Item
1 Telephone line-in
2 Telephone line-out
Some modem adapters may come
without this jack.
3 Voice-in/speaker-out connector
NOTE: Care should be taken while connecting the voice-in/speaker-out
connector. The longer exposed end (about. 15mm) of the cable should
be connected to the modem card. The other end should be connected to
the system board.
156
Function Connect to...
Telephone line
Telephone set
System board
Machine Type 2170: CN 21
Machine Type 2171 and 2172:
CN12