What Causes Frequent Cycling of Car Air Conditioning?
2 Answers
Car air conditioning frequently cycling on and off can be attributed to the following reasons: 1. Pressure Issues: When the pressure within the air conditioning system exceeds 24 BAR or falls below 2.4 BAR, the pressure switch will control the compressor to shut down. If the system pressure is too high or too low, the cooling effect of the air conditioning will be poor. Therefore, the pressure switch is a likely culprit. 2. Power Issues: When the engine lacks sufficient power (such as when the engine speed is too low, too high, or during rapid acceleration), the engine ECU controls the compressor to stop working via the 822 relay. Keep the throttle at 1500 RPM and observe whether the air conditioning compressor starts frequently. If it still starts frequently, the issue is not related to this aspect. If the compressor operates normally, then the engine system (idle valve, fuel injector, spark plugs, etc.) should be checked.
My old car's AC keeps cutting off, it automatically shuts down after running for a while, so annoying. When I took it for repairs, the mechanic said the most common issue is insufficient refrigerant due to leaks, requiring a refill and reseal. Another possibility is the compressor's thermal protection kicking in—it shuts off when overheated to prevent damage. Worn-out wiring, loose connections, or a faulty pressure switch could also cause this. I cleaned the AC filter myself; if it's too dirty and blocks airflow, the evaporator can freeze up and the AC stops. It's recommended to check refrigerant levels every six months and perform timely maintenance to avoid major repairs. Extra caution is needed in summer—don't wait until a long trip for problems to arise. After the overall repair, the car feels much more comfortable; it didn't cost much but saved a lot of hassle.
