To repair a broken wire from a Lowrance X25A to the transducer, you can first locate the break by inspecting the wire along its length. Once found, strip the insulation from both ends of the broken wire, twist them together, and secure with solder for a strong connection. Use heat shrink tubing or electrical tape to insulate the repaired area and prevent future damage. If you're not comfortable making the repair, consider seeking help from a marine electronics technician or contacting Lowrance for assistance.