What causes the air conditioning to stop working at 3000 RPM?
2 Answers
When the air conditioning stops working at 3000 RPM, it is due to excessive pressure. Solutions for air conditioning failure caused by engine overheating: When using the air conditioning, the engine operates under high load conditions. The air conditioning compressor increases the engine load, and the condenser requires the cooling fan for forced heat dissipation. Therefore, engine temperature is a critical parameter for the air conditioning system. When the engine temperature is too high, the engine control unit will disconnect the ground terminal of the air conditioning compressor relay to reduce the engine load and lower the temperature. Main causes of high engine coolant temperature: 1. System contamination or blockage, such as internal obstruction in the radiator tank. 2. Mechanical blockage, such as malfunctioning or damaged thermostat, or poor performance of the water pump. 3. Air lock, where engine failure causes high-pressure gas to enter the cooling system. 4. Poor heat dissipation, such as low cooling fan speed, damaged fan shroud, or dirty radiator surface. 5. Vehicles with electric fans may experience delayed cooling fan activation, which is a primary cause of high coolant temperature in small cars.
I reckon when the engine hits 3000 rpm and the AC cuts out, nine times out of ten it's the AC compressor acting up. Any seasoned driver knows the compressor relies on the engine to spin it—if its clutch coil burns out or the wiring comes loose, it won't engage at high revs. Another possibility is the belt being as loose as an old lady's waistband, slipping and failing to drive the compressor when the revs climb. I should remind you to check the cooling fan too—if the radiator fins are clogged with poplar or willow fluff, the system might overheat and automatically shut off the AC. Oh, and once my car had the same issue—plugged in the scanner and found the pressure switch acting erratic, with wild pressure swings in the AC lines tripping the protection mode. These kinds of gremlins are tough to DIY; I always just drive straight to the shop and let the mechanics test the refrigerant levels with gauges, while also checking if the temp sensor's feeding false intel.
