Info - A/C System Oil Circulation Procedure to Avoid Premature A/C Compressor Wear

This bulletin is being revised to update the A/C System Oil Circulation Procedure. Please discard Corporate Bulletin Number 05-01-38-002A (Section 01 - HVAC).

Lack of proper lubrication to the new A/C compressor may cause pre-mature wear on some vehicles in new car inventory.

This condition is caused by refrigerant system oil migration (compressor wash-out), which occurs on brand new vehicles that have not had the air conditioning system on for an extended period of time (typically for times greater than 100 days). For vehicles in this category, the A/C system should not be run until the A/C compressor oil circulation procedure has been performed.

This condition is not a quality concern that can be fixed by the replacement of the compressor or by the addition of refrigerant oil to the system. It is a condition caused by the vehicle sitting outside, in the sun, for extended periods of time. Thermal cycling causes the oil in the A/C compressor to migrate to the other A/C system components. This condition does not occur on A/C components stored in service inventory, such as A/C compressors. Continue to use all service components for this vehicle as normally instructed.

It is recommended that vehicles are started and the A/C system is operated (for at least 90 seconds) every 90 days, to ensure proper A/C system function until the vehicles are delivered or such time that the vehicle is driven on a regular basis. Normal operation of the A/C system by the vehicle owner will allow for sufficient compressor break-in and the oil circulation procedure should no longer be required.

DO NOT ADD ADDITIONAL REFRIGERANT OIL TO THE A/C SYSTEM.

PERFORM A/C SYSTEM OPERATION TO ENSURE PROPER LUBRICATION OF THE A/C COMPRESSOR DURING THE INITIAL VEHICLE STORAGE PERIOD.

Perform the following sequence to ensure proper lubrication of the A/C compressor during new vehicle extended periods of in-operation. It is required that this procedure be performed early in the morning when the vehicle is cold and ambient temperature is moderate (approximately 10°C (50°F)).

Important:  The A/C system will not operate when the ambient temperature is below 2°C (35° F).

1. Make sure air conditioning (A/C button) is off.
2. Put the mode selector in the vent mode.
3. Start vehicle and let engine RPM idle down to slow idle RPM (1000 RPM or less).
4. Adjust the HVAC blower setting to high.
5. Turn on the air conditioning and allow the system to run for 90 seconds. This gradual A/C system operation period will allow the refrigerant oil to return to the A/C compressor during the critical initial break-in period.