2022-2023 Audi A3, S3, RS 3 HVAC Musty Odor TSB

Owners of 2022-2023 Audi A3, S3, and RS 3 vehicles may notice an unpleasant, musty odor coming from their heating and ventilation system. This issue is addressed by Audi Technical Service Bulletin (TSB) 2069903/1, which outlines the cause and the necessary inspection and repair procedures.

Symptoms

The primary symptom is an unpleasant, musty odor originating from the vehicle's heating, ventilation, and air conditioning (HVAC) system. This Audi S3 musty odor can be particularly noticeable when the system is operating.

Technical Background

According to TSB 2069903/1, the root cause of the musty odor is a structural issue within the heater, air conditioning, and air distribution housing. This design flaw allows moisture to accumulate inside the housing. The drainage and evaporation efficiency of the system is insufficient to prevent this moisture buildup, leading to the development of the unpleasant smell.

Audi has implemented an improved heater, air conditioning, and air distribution housing in production vehicles to prevent this issue in newer models.

Diagnosis and Trigger Conditions

To diagnose the source of the Audi S3 musty odor, technicians will perform several inspections to identify evidence of water intrusion in the HVAC system. The process involves:

• Glove Compartment Removal: The glove compartment is removed to access the HVAC components.
• Dust and Pollen Filter Inspection: The dust and pollen filter is removed and inspected for any signs of water damage or contamination. A normal filter would appear clean, while a contaminated one would show water stains.
• Fresh Air Blower V2 Removal: The fresh air blower (V2) is removed to allow for further inspection.
• Blower Housing Inspection: The inside of the fresh air blower housing is carefully inspected for undrained water. Technicians specifically look at the lowest point of the left section of the housing. A borescope may be used to get a clear view of pooled or dried water within the housing.

Borescope images may show clear evidence of water intrusion into the fresh air blower housing, confirming the presence of moisture.

Repair Procedure Summary

If the inspections reveal evidence of water intrusion, undrained water staining, or water contamination of the dust and pollen filter, the entire heater, air conditioning, and air distribution housing assembly must be replaced. This comprehensive replacement includes several key components:

• The air intake housing
• The evaporator housing
• The air distribution housing
• A new dust and pollen filter
• A new fresh air blower V2

This ensures that all affected parts contributing to the Audi S3 musty odor are addressed.

Required Parts and Tools

To perform the repair outlined in TSB 2069903/1, specific parts and tools are necessary:

Required Parts:

• 5WB898304: Air Intake Duct
• 5Q1820007D: Housing
• 5QB820353A: Air Distribution Housing
• 5Q0819669: Dust and Pollen Filter
• 5WB819021A: Fresh Air Blower

Required Tools:

• T40207: Hook Tool
• T10532: Blower Motor Cover Plate

Always confirm the latest part numbers and availability with your Audi Parts Department.

Warranty Information

This repair, identified by Service Number 8515 and Damage Code 0050, is covered under warranty for vehicles up to 48 months or 50,000 miles. For Audi Certified Pre-Owned (CPO) vehicles, the claim type G10 applies, subject to owner verification. All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual.

Important Warnings

If your vehicle is outside of its warranty period, this Technical Service Bulletin is for informational purposes only. Owners should be aware that repairs may not be covered if the vehicle is past the specified mileage or time limits.

Owner Action

If you experience an unpleasant, musty odor from your 2022-2023 Audi A3, S3, or RS 3's HVAC system, contact your authorized Audi dealership. Inform them about the symptom and refer to Technical Service Bulletin 2069903/1. The dealership technicians will perform the necessary inspections and repairs to resolve the Audi S3 musty odor issue.

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Source: NHTSA ID: 10234571