What Causes the Intermittent Operation of BMW 5 Series Air Conditioning?
3 Answers
The intermittent operation of the air conditioning depends on whether the compressor is functioning. When the compressor is working, it produces cool air; when it is not, only natural air is delivered. Below is relevant information: 1. Reasons for compressor failure: The compressor load is too high, triggering the overcurrent protector and causing a power shutdown. A motherboard control malfunction intermittently starts the compressor. Air in the system is not completely purged, leading to excessively high pressure, which activates the high-pressure protector and shuts down the system. 2. Reasons for abnormal air output: The automatic mode may be enabled, causing the system to shut down when the set temperature is close to the room temperature. This creates a false impression of a malfunction where the system turns off shortly after starting, when in fact, the air conditioning is not faulty. Unstable or abnormal voltage may also be a cause. The compressor's overcurrent protection could be triggered. It is recommended to try using a voltage stabilizer. The indoor coil temperature is too high, leading to protective shutdown. When the indoor temperature is 26 degrees and the outdoor temperature is above 20 degrees, the air conditioning cannot heat properly, making it prone to protective shutdowns.
My BMW 5 Series air conditioning had this intermittent issue before. After repairs, common causes were found to include poor contact in the compressor clutch leading to intermittent cooling failure (sometimes it wouldn't engage properly), slow refrigerant leakage causing insufficient pressure that temporarily affected cooling performance, electronic control module faults like malfunctioning temperature sensors triggering false errors, aging blower motor resistors causing unstable fan speeds, and condenser blockages or dirt buildup affecting heat dissipation. I recommend immediately visiting a professional shop for diagnosis using an OBD scanner to read trouble codes - don't let small issues escalate. Regularly replacing cabin air filters and cleaning the system can prevent this. After my experience, I've developed a habit of getting pre-summer inspections annually.
Driving a BMW 5 Series on the highway, the air conditioning suddenly stopped blowing cold air, then worked again after a while, which was quite annoying. I've experienced this issue before. The root causes could be: a faulty fan control module that sometimes overheats and stops working; a leak in the refrigerant circulation system causing gas to slowly escape; temperature sensor errors leading to system shutdowns; or loose electrical connections. The mechanic suggested doing some self-checks first: feel the compressor pipes—if they vibrate normally, it might indicate an electrical issue; listen for unusual noises from the blower. Don’t tinker blindly, especially with BMW’s precise electronic components—wrong fixes could make things worse. In the end, I replaced the control unit and the problem was solved, saving me a lot of hassle and time.
