What are the symptoms of a faulty car air conditioning relay?
2 Answers
Car air conditioning relay failure manifests as: 1. Inability to start the car air conditioning; 2. Compressor failure to operate; 3. Occasional startup without cooling function. Car air conditioning refers to the climate control system installed in vehicles, capable of cooling, heating, ventilating, and purifying cabin air to provide passengers with a comfortable environment, reduce driver fatigue, and enhance driving safety. Typically comprising refrigeration units, heating systems, and ventilation devices, this integrated system efficiently utilizes limited vehicle space with simple structure and user-friendly operation.
When the car's AC relay fails, the interior becomes as hot as a steamer. I've encountered this several times. The most obvious sign is that the AC doesn't respond at all—the fan doesn't spin, and the compressor doesn't start. Sometimes, you can hear a faint clicking sound from under the car, especially when starting or waiting at a red light. If the fuse blows as well, the entire system shuts down, making driving in hot weather unbearable. The relay is usually located near the fuse box, in a small black box. It's best not to attempt a DIY fix—just drive to a nearby repair shop and let professionals replace it, saving hassle and ensuring safety. During routine maintenance, simply mention this issue—prevention is the most worry-free approach.
