A valve that will not shut is urgent. The lid is the part that makes it slow. In shaded Grapevine side yards, St. Augustine runs over a green box in one season. Mulch does the same job in a downtown courtyard. By July the only clue is a square of deeper green, or the sound of water when that station should be off.
We do not start at the controller and condemn it. A stuck valve still clicks a solenoid. We find the box from the wire path and from the wettest soil, then lift the lid and service the valve that is actually failed. Replacing a clock because the grass ate the box is a common wasted visit.
After the diaphragm or solenoid is done, the lid goes back where a mower can miss it and a person can find it. If the box was crushed, the replacement is part of the same repair. Leaving a cracked lid is how dirt packs the next valve.
If you already know the box is along the left fence, say so. If you have never seen a lid, say that too. Both are normal on this call. The number is (469) 294-8444, and the service page is valve repair.