2022-2023 Audi Models HVAC Musty Odor TSB

Symptoms

Owners of 2022-2023 Audi models may notice an "unpleasant, musty odor coming from the heating and ventilation system." This Audi HVAC musty odor typically manifests under specific conditions:

• The odor usually occurs after the vehicle has been sitting unused for five hours or more.
• The smell often appears within 20 to 60 seconds after the vehicle is started.

Technical Background

Condensation is a normal byproduct of all A/C systems, and it can lead to a musty odor. It's important to differentiate this from other potential sources of odor, such as mold or mildew in the passenger compartment unrelated to the A/C system. Before performing the cleaning procedure, other possible odor sources must be investigated and ruled out.

Important Warnings for Owners

Audi has specific conditions regarding this service bulletin:

• This cleaning procedure is allowed only once per vehicle.
• The vehicle must be within its first 12 months of service and covered under the New Vehicle Limited Warranty (NVLW).
• An original customer concern regarding the specified odor symptom must be documented on the repair order for this bulletin to apply. Dealers are not permitted to add this procedure without a customer complaint.
• Any subsequent applications of this procedure, should they become necessary, will be the customer's responsibility and not covered under warranty.
• Replacement of the pollen filter under warranty is not allowed as part of this procedure. The pollen filter is only covered if specified at the appropriate maintenance interval.

Repair Procedure Summary

To eliminate the Audi HVAC musty odor, Audi specifies a specialized cleaning process using the Aircomatic® II Ultrasonic Climate System Cleaner (VAS 6189A) and Airco-Clean® Ultrasonic Air Conditioning Treatment (VAS 6189/1). No other cleaning methods are permitted.

The high-level procedure involves several steps:

1. Preparation: If your vehicle is equipped with an in-cabin pollen filter, it must be removed, and its cover reinstalled before proceeding.
2. Vehicle Setup: Start the engine and adjust the climate control settings. This includes setting the temperature to its lowest, fan speed to its lowest, airflow to dash vents only, and activating recirculation and ECON modes (as shown in Figure 1 of the TSB).
3. Treatment Application: A 100ml bottle of Airco-Clean® treatment is thoroughly shaken and emptied into the filling chamber of the Aircomatic® unit (Figure 2).
4. Unit Placement: The cleaning unit is placed level in the passenger side footwell, and its outlet tube is connected (Figure 3). The unit's power cord is routed through a slightly open window, with all other windows and the sunroof completely closed (Figure 4).
5. Cleaning Cycle: The unit is turned on, and the outlet tube is positioned so that the vapor is drawn into the recirculation air intake. All doors are closed. The atomized cleaning fluid will then be emitted from the vents. The treatment typically takes 15-20 minutes, after which the machine automatically stops.
6. Dual Evaporator Systems: For vehicles equipped with a four-zone climate control system and two evaporators (such as the Audi Q7 and A8), the procedure must be repeated for the rear A/C unit. The outlet tube should be positioned towards the fresh air inlet vent for the rear unit (Figure 5).
7. Post-Treatment: After the cleaning cycle, the vehicle should be aired out for approximately ten minutes.
8. Maintenance: Technicians should consult the Aircomatic® manual for instructions on maintaining the unit after each use.

Required Tools and Parts

To perform this cleaning procedure, specific Audi-approved items are necessary:

• Part Number VAS 6189/1: Airco-Clean® Ultrasonic Air Conditioning Treatment (100ml bottle). One bottle is required for models with a single evaporator, and two bottles for models with two evaporators.
• Tool Number VAS 6189B: Aircomatic® II Ultrasonic Climate System Cleaning unit.
• Other: Fasteners, bolts, nuts, and screws as needed per the Repair Manual (refer to ETKA/ELSA for specific details).

Warranty Information

For vehicles under warranty, the following claim details apply:

• Claim Type: 1SP
• Service Number: 8760
• Damage Code: 0049
• Labor Operations:
  • A/C clean - All models with single evaporator: 8701 2999 (70 Labor Time Units)
  • A/C clean - All models with two evaporators: 8701 3099 (135 Labor Time Units)
  • Audi R8 A/C clean: 8701 0599 (210 Labor Time Units)
• Diagnostic Time: GFF (No allowance, 0 Labor Time Units)
• Road Test Time: No allowance for road tests prior to or after service (0 Labor Time Units).
• Claim Comment: As per TSB 2010146/17

Owner Action

If you are experiencing a Audi HVAC musty odor in your 2022-2023 Audi model, it is recommended to contact your authorized Audi dealer. Describe the symptoms clearly, noting when the odor occurs. Be aware of the warranty conditions mentioned above, as this procedure is typically covered only once and within the first 12 months of service under the New Vehicle Limited Warranty.

NHTSA ID

This article is based on NHTSA document 10210526.