How to Prepare an RJ12 Crimp Connector Cable

By Connie s Owens

The RJ12 is a telephone line.
i RJ-11 telephone cable image by TekinT from

The RJ12 cable is manufactured with four and six wires. The four-wire cable is traditionally used for voice transmission with a telephone service, while the six-wire cable is capable of transmitting both voice and data. The six-wire cable is traditionally used to connect networks. Preparing your RJ12 crimp connector cable whether it is six or four wires requires the same steps.

Step 1

Strip the end of the telephone wire of the plastic outer coating using the modular crimp tool's blade section. The length will range from an eighth to a quarter of an inch.

Step 2

Strip the color wires, one at a time, using the modular crimp tool. To keep from breaking the fine wires, carefully apply pressure when pulling the plastic coating off of the wire.

Step 3

Place each wire into the modular plug matching the colors. Push the wire as far as it will go -- be careful to not break the fine wires. Repeat for each color.

Step 4

Crimp the modular plug using the crimping tool. Do not squeeze too hard to keep from breaking the plug.

Step 5

Plug your RJ12 connector into the telephone jack and telephone. Or plug the RJ12 six wire into the modem of your computer and other network modules.