RJ11 and RJ45 Wiring Instructions - Xmultiple The typical RJ-11 connector has six terminals. Usually, only the middle four pins are used. The POTS (Plain Old Telephone Service) residential telephone wiring generally contains two pairs of wires - designed for two separate telephone lines. The center pins (Red and Green) contain the first telephone line. Rj11 Wiring Diagram Using Cat5 | Free Wiring Diagram Assortment of rj11 wiring diagram using cat5. A wiring diagram is a simplified standard photographic depiction of an electrical circuit. It shows the elements of the circuit as streamlined shapes, and the power and signal links in between the tools.