how to fix the AC not blowing cold air in BMW 3 Series E90/E91 (2005-2012)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety during the repair.

2. Recharge the AC System

• Tools Required: AC refrigerant gauge, refrigerant canister, manifold gauge set.
• Connect the refrigerant gauge to the low-pressure port of the AC system.
• Check the pressure readings; if low, proceed to recharge.
• Start the engine and turn on the AC to maximum settings.
• Add refrigerant according to the manufacturer’s specifications until the pressure reaches the appropriate level (typically 30-40 PSI on low side).

3. Inspect and Replace AC Compressor (if necessary)

• Tools Required: Socket set, screwdriver set, torque wrench, AC compressor replacement.
• Remove the drive belt by loosening the tensioner pulley.
• Disconnect the electrical connector and refrigerant lines from the compressor.
• Unbolt the compressor from the mounting brackets.
• Install the new compressor by reversing the removal steps, ensuring all connections are secure.
• Torque the bolts to manufacturer specifications.

4. Inspect and Clean AC Condenser

• Tools Required: Pressure washer or air compressor, cleaning solution.
• Inspect the condenser for debris or damage.
• If dirty, clean the condenser carefully with a pressure washer or air compressor.
• Ensure the condenser fins are straight and unobstructed for optimal airflow.