Curtain rods operate with a cord system to open and close the curtain panels. Eventually, the pull cords can begin to wear out and may break due to pulling the fabric to open or close the curtains rather than using the cord. You can replace the cord instead of purchasing new curtains.
Lift the curtains out of the rod brackets and place on a table. Unhook the pull cord from the tension pulley next to the window. Take the rod assembly off the brackets and place it face down on a flat surface.
Draw a letter "A" on the backside of the master carrier A with a permanent marker. The master carrier is the rectangle-shaped plastic box furthest away from you. Mark the closest box to you as the master carrier B by drawing a "B" on it.
Snip the cord just above the knot with scissors and discard the end pieces. Feed the new cord through the top right opening of master carrier A and tie the end of the cord. Pull the cord to the right and bring it over the top of the pulley. Pull the cord down to the left between the first and second pulley.
Push the cord through the bridge of master carrier B and pull it to the left between the first and second pulley. Pull the cord through and lift it above the top pulley and bring it to the right. Feed the cord through the top right hole of master carrier A and tie a knot in the end. Set the curtain rod in the brackets.
Push the cord through the tension pulley, which is usually mounted to the side of the cords.
Gently tug on the cord until master carrier A is on the far right side. Firmly hold both cords in your hands. Pull the cord until master carrier B is on the far left, then lock the cord with the lock on the back of master carrier B.
Take the knot out of the opening on the right side of master carrier A. Tug on the tension pulley until the cords are taut. Make a new knot near the master carrier A right-side hole. Pull on the cord and test it. Cut off any extra cord and re-hang your curtains.