DEFINITION: Noise originating from the A/C compressor, drive belt or the A/C lines.

Were you sent here from HVAC Symptoms or another diagnostic table?

Go to Step 2

Go to Diagnostic System Check - Vehicle.

Inspect and if necessary rectify any faults with the accessory drive belt and drive belt tensioner.

Go to Step 3

Run the engine and check for possible compressor noise.

Does the noise last longer than 30 seconds?

Go to Step 5

Go to Step 4

Is any noise detected using this procedure?

Go to Step 6

It is normal to observe a liquid sludging condition. This may occur after extended system shut down at warmer ambient temperatures, followed by an overnight ambient temperature drop

Check if the system has a low refrigerant charge.

Is there enough system gas?

Go to Step 7

Go to Step 8

Check if the thermostatic expansion (TX) valve is stuck closed or open.

Is the TX valve stuck?

Carry out TX valve diagnosis. Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement.

Go to Step 7

Check for any loose compressor bolt and/or A/C plumbing contacting the bodywork.

Is there any A/C plumbing contacting the bodywork or mounting bolts loose?

Tighten bolts and/or relocate plumbing

Go to Step 8

1. Recover refrigerant and replace compressor.
2. Recharge the system

Are the gas pressures within specification?

System checks complete

Go to Step 1