2021-2023 Audi e-tron AC Compressor Noise TSB

Audi has issued Technical Service Bulletin (TSB) 2063467/6 to address a common complaint of noise emanating from the air conditioning compressor when the AC system is active in certain e-tron models. This TSB, dated April 18, 2024, supersedes a previous bulletin, 23-49, from August 9, 2023, and provides updated guidance for diagnosing and resolving the issue.

Symptoms

Owners of affected Audi e-tron vehicles may notice a distinct "noise heard in the cabin when the air conditioning system is active particularly when the air conditioning compressor is running. When the air conditioning system is turned off the noise is eliminated." This Audi e-tron AC noise is typically reproducible and does not originate from within the cabin itself.

Technical Background

The primary cause of the Audi e-tron AC noise is often direct contact between various components in the engine bay. The TSB identifies several potential contact points that can transfer vibrations from the AC compressor into the cabin:

• Refrigerant Lines: Adjacent refrigerant lines may be making direct contact (Figure 1, Figure 3, Figure 4), leading to noise and vibration. This can also occur between a coaxial refrigerant line and the refrigerant line containing the service port (Figure 8).
• Bowden Cable Clip: A refrigerant line might be in contact with the Bowden cable clip for the front hood release in the front motor compartment (Figure 2, Figure 7).
• Compressor Isolator: The compressor isolator spring might not be correctly indexed in its rubber mounting, causing an incorrectly seated compressor isolator assembly (Figure 9). This can lead to vibration transfer.
• Service Port Mounting Block: Interference between the service port mounting block and an adjacent line can also generate noise (Figure 11).

Repair Procedure Summary

To resolve the Audi e-tron AC noise, technicians should follow the steps outlined in TSB 2063467/6, focusing on identifying and eliminating contact points:

1. Separate Refrigerant Lines: Inspect for any adjacent refrigerant lines that are making contact. If found, these lines must be separated and secured in a separated position using a hose holder, clip, or tie-wrap (Figure 5, Figure 6). This also applies to contact points between coaxial refrigerant lines and service port lines (Figure 8).
2. Address Bowden Cable Clip Contact: If a refrigerant line is contacting the Bowden cable clip for the front hood release (Figure 7), these components must be separated and secured. The retaining clip for the refrigerant line allows it to slide, so it should be secured away from the Bowden cable clip.
3. Inspect Compressor Isolator Assembly: Examine the compressor isolator/spring assembly for proper seating. If the isolator spring is not correctly indexed in the rubber mounting, it will appear poorly seated (Figure 9). The spring and/or rubber mount may need to be twisted to correct the indexing, ensuring the isolator assembly lies flat against the bracket (Figure 10).
4. Correct Service Port Mounting Interference: If the service port mounting block is interfering with an adjacent line (Figure 11), technicians should push the service port in the direction indicated to create a permanent clearance (Figure 12).

Warranty Information

Warranty claims for this repair are covered under specific conditions. For vehicles within 48 months or 50,000 miles, the claim type is 110. For Certified Pre-Owned (CPO) vehicles, the claim type is G10, and owner verification is required. The Service Number for this issue is 8744, and the Damage Code is 0020. Labor operations include removing and reinstalling the front storage compartment (7007 1900), separating and securing refrigerant/coolant lines (8744 1399), and correcting compressor isolator positions.

Important Warnings

Owners should be aware that if their vehicle is outside of any applicable warranty, this Technical Service Bulletin 2063467/6 is for informational purposes only. Any repairs performed would likely be at the owner's expense.

Source: NHTSA ID 10253974