How a Venetian Blind Cord Lock Works If your Venetian blind won't stay up, slips down after raising, or the cords seem locked and blind is stuck, the cord lock mechanism is often the cause. Understanding how the cord lock works can often help diagnose faults and make recording / repairing much easier. What Is a Venetian Blind Cord Lock? The cord lock is the small mechanism usually fitted inside the headrail that grips the lift cords and holds the blind at your chosen height.

Common causes Vertical Blind won't rotate correctly.