DFW & Surrounding Areas
A loop detector is a wire loop cut into your driveway and a small board that senses metal above it. When it misbehaves the cause is nearly always water, a cracked slab, or sensitivity that no longer matches the vehicles using it.
How we approach loop detector not working
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A failed exit loop usually means vehicles cannot get out without a remote. On a commercial site that backs traffic onto the road, which makes it urgent rather than merely inconvenient.
Some causes of loop detector not working you can resolve yourself in minutes. We would rather you found one than paid us to.
Most detectors show detection state on an LED, and many show a distinct fault or open-loop pattern. Detection showing with nothing over the loop, or a fault pattern, tells you which of the two symptom families you have before anyone opens anything.
If a truck triggers it and a compact car does not, the loop is intact and the sensitivity is wrong. If nothing triggers it, the loop or the detector has failed. That is a genuinely useful split and it costs you two minutes.
Note whether the fault appears in the wet and clears when dry. Water in a splice is the most common cause in this climate and the weather correlation identifies it almost on its own.
The saw-cut loop is usually visible as a sealed rectangle in the slab. A crack crossing that line is a strong candidate for a broken conductor, and it tells us to quote a re-cut rather than a tune.
Checked all that and it is still loop detector not working?
Tell us what you found — it shortens the visit.
A loop is several turns of wire laid in a saw-cut slot in the driveway and sealed over. The detector energises that loop and watches its inductance. A large mass of metal above it — a vehicle — changes the inductance, the detector notices the change, and it closes a contact that tells the gate to open or holds it open while the vehicle passes.
That means a loop detects metal, not weight and not presence. A motorcycle, a bicycle or a person will often not trigger it at all, which is normal behaviour rather than a fault. It also means anything that changes the loop’s electrical characteristics — water, a break, a crack in the slab that stretches the wire — looks exactly like a vehicle.
A loop fault shows up in one of two ways. Either the detector stops seeing vehicles, so the gate will not open for a car sitting right on top of the loop, or it sees a vehicle permanently, so the gate opens by itself or refuses to close.
Both come from the same short list: water in the loop or its splice, a broken conductor, a cracked slab, or a detector whose sensitivity has drifted or was set for different traffic. Which symptom you get depends on whether the change pushed the inductance up or down, which is why a single wet splice can present either way.
Each of these looks different at the gate. The “how to tell” line is what separates it from the one above.
Most loop faults are repaired at the splice or the detector and cost little. The expensive outcome is a broken conductor in the slab, which needs the loop re-cut, and we would rather tell you that plainly than take payment for a third re-tune of a loop that is electrically broken.
Driveways across much of Dallas–Fort Worth are laid over Blackland Prairie clay that swells and shrinks by season. Slabs crack along that movement, and a loop cut into a slab that is moving will eventually be stretched or severed where a crack crosses it. This is why loop failures here are disproportionately physical rather than electronic.
The same seasonal swing drives water into the cut. A wet spring after a dry autumn opens and then floods the sealant line, and the splice is the first thing to suffer. Storm surges take out the detector modules themselves. Between the three, loops in this metroplex need checking more often than the equipment’s design life would suggest.
Not necessarily. First check whether a larger vehicle triggers it. If a truck works and a small car does not, the loop is intact and the detector sensitivity needs re-tuning. If nothing triggers it, then the loop or the detector has genuinely failed and we can tell which by testing the loop.
Water has almost certainly reached the loop or its splice. The detector senses a change in the loop and reads it as a vehicle, so it calls for open — sometimes repeatedly, for as long as things stay wet. Drying and resealing the splice is usually all it takes.
Usually not. Most loop faults are at the splice or in the detector, both of which are repaired without touching the slab. Cutting is only needed when the loop conductor itself is broken, and we will show you the test result that says so before recommending it.
That is normal. A loop detects metal mass, and a motorcycle presents far less of it than a car. Sensitivity can sometimes be raised enough to catch one, but raising it too far causes the gate to open for traffic on the road, so on many sites the honest answer is to use a remote or keypad instead.
A properly installed loop in stable ground lasts many years. In this region the limiting factor is usually the slab rather than the wire — once a driveway starts cracking over moving clay, the loop’s life is tied to the concrete’s. That is worth knowing before paying for a premium detector to sit on a failing loop.
Include what you found in the checks above — where it stops, what you heard, whether it moves by hand. It genuinely shortens the visit, and it means we arrive with the right part more often.
We answer the phone 24/7. If you are stuck, call and we will talk you through the manual release before anyone arrives. See what counts as a gate emergency.
