If your telephone is polarity sensitive, follow the procedure below:
1. Complete all the required extension wiring.
2. Confirm that dialing can be done from all the
extensions using a touch-tone telephone.
If dialing fails, the polarity between the extension
and the system must be reversed.
3. Reverse as shown.
4. Unplug the system.
5. Connect all outside lines.
6. Confirm that dialing can be done on the following
extension using a touch-tone telephone.
Extension (T, R) of jack 01: Outside (CO) line 1
If dialing fails, the polarity between the system and
the outside line must be reversed.
7. Reverse as shown.
8. Every time an extension telephone is replaced,
repeat the procedure above.