my Toyota Corolla E140 (2006-2013) is making a hissing noise when I turn on the AC

Solution

1. Preparation

• Gather necessary tools and parts. Ensure the vehicle is parked on a level surface and the engine is off.
• Safety warning: Disconnect the battery before working on electrical components.

2. Inspect and Replace AC Components

a. Inspect AC Hoses

• Tools Required: Visual inspection tools (flashlight, mirror)
• Check all AC hoses for signs of wear, cracks, or leaks. Pay close attention to the connection points.
• If any hoses are damaged, replace them.

b. Check and Recharge Refrigerant

• Tools Required: Manifold gauge set, refrigerant canister
• Connect the manifold gauges to the low and high-pressure service ports.
• If the refrigerant level is low, follow the manufacturer's specifications to recharge the system with the correct type and amount of refrigerant.

c. Inspect and Replace the AC Compressor

• Tools Required: Socket set, torque wrench
• If the compressor is found to be faulty (based on sound and pressure readings), remove it by disconnecting the refrigerant lines and electrical connectors.
• Install the new compressor, ensuring to torque all bolts to the manufacturer's specifications.
• Recharge the AC system with refrigerant.

3. Reassemble and Test the AC System

• Reconnect the battery and start the engine.
• Turn on the AC to check for proper operation and confirm that the hissing noise has ceased.