why is my BMW 3 Series F30/F31 (2012-2019) AC not blowing cold air anymore?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety during repairs.
• Allow the vehicle to cool if it has been running.

2. Recover Refrigerant

• Use a refrigerant recovery machine to safely remove refrigerant from the system.
• Connect the recovery machine to the low and high-pressure service ports.
• Activate the recovery machine according to the manufacturer's instructions.

3. Inspect and Repair Leaks

• Visually inspect all AC components for signs of leakage (e.g., oily residue).
• If a leak is found, replace the affected components (e.g., O-rings, hoses, condenser).
• Use UV dye to detect leaks if necessary.

4. Replace Cabin Air Filter

• Locate the cabin air filter housing (usually behind the glove box).
• Remove the glove box if necessary to access the filter.
• Replace the old cabin air filter with a new one, ensuring proper orientation.

5. Recharge the AC System

• Connect the refrigerant supply canister to the low-pressure service port.
• Begin charging the system with the appropriate type and amount of refrigerant (usually R-134a).
• Monitor the low and high-pressure gauges to ensure the system is charged correctly.

6. Test the AC System

• Reconnect the battery and start the vehicle.
• Activate the AC system and observe for cold air blowing from the vents.
• Verify that the AC compressor is engaging and that there are no unusual noises.