I have a 2018 CRV LX 2.4L with 141k miles on it. The AC is blowing hot air and I hear a hissing sound coming from the vents and from the side of the engine facing the cab. Before this happened the air would go from hot to cold and now finally it's all hot air. The pulley's are turning under the car but I can also hear hissing from the back of the engine facing the cab area. What is the most likely issue?
What is the most likely issue?
There is no single most likely issue when dealing with air conditioning problems. It is necessary to perform diagnostics to determine the cause.
Have you checked your high and low system pressures? Refrigerant may have leaked out. That vehicle uses the new R1234YF refrigerant, which is very expensive and you would need a compatible gauge set to check (unique fittings are used). Is the AC compressor clutch engaging?
You can do some diagnostics with temperatures of various AC components:
That system is computer controlled so the problem could be in the electronics. There could be a problem with your temperature blend door, sensors, or the HVAC control module. A professional-grade bidirectional scan tool would be required for diagnosing the electronics.
If you are not familiar with working on air conditioning it would be best to take the car to a good independent shop for diagnosis and repair.
