Posted on 2/27/2026
A/C leaks usually do not announce themselves with a big puddle or an obviously broken part. Most of the time, cooling just slowly gets weaker, especially on hotter days or when you are sitting in traffic. That slow change is why people end up topping off refrigerant more than once, even though refrigerant does not get used up. When you find the leak early, the repair is usually simpler, and the A/C stays cold longer. Why Dye Testing Works For A/C Leak Finding Dye testing works because most A/C leaks carry a little bit of refrigerant oil with them. A UV dye is added to the system, then the vehicle is run normally so the dye circulates with the oil. If refrigerant escapes, the dye tends to leave a trace at the leak point. Under a UV light, that trace stands out clearly, even when the leak is too small to spot with the naked eye. This approach is especially helpful for slow leaks that only show up under certain temperatures and pressures, which is common in real-wor ... read more