Damaged garage door lift cables must be replaced, they cannot be repaired. People can replace lift cables themselves or hire a professional handyman or garage door sales and service company to do the work.
Homeowners who replace damaged lift cables themselves can save a lot of money on repairs. Depending on the type of garage door involved, lift cable costs range from a few dollars to around $30. Working with the springs in a garage door can be dangerous, so DIY replacement requires some mechanical expertise. Insert a winding bar into the spring's winding cone and loosen the screws. Use the winding bar to hold the spring in place. Do this for both springs, and the winding shaft should be freed for movement, allowing for cables to be replaced.