2021 Audi e-tron Musty A/C Odor TSB 2010146/15

Symptoms

Owners of affected 2021 Audi vehicles, including the e-tron, may notice an "unpleasant, musty odor coming from the heating and ventilation system." This odor typically appears after the vehicle has been sitting unused for five hours or more. It usually becomes noticeable within 20 to 60 seconds after the vehicle is started.

Diagnosis / Trigger Conditions

The root cause of the "2021 Audi e-tron musty A/C odor" is often condensation within the air conditioning system. This condensation can create an environment conducive to the growth of mold and mildew, leading to the musty smell. If the odor is present even when the engine is off, it might indicate mold or mildew in the passenger compartment unrelated to the A/C system itself.

Before performing the cleaning procedure outlined in TSB 2010146/15, technicians are instructed to check several areas. These include ensuring the evaporator housing drain is open and free of debris, confirming the cabin is sealed against water ingress, verifying that plenum drains are clear, and checking that the pollen filter is clean and dry. Addressing these potential issues first helps ensure the cleaning treatment is effective.

Repair Procedure Summary

Technical Service Bulletin 2010146/15 outlines a specific cleaning process to eliminate the "2021 Audi e-tron musty A/C odor." This procedure utilizes the Aircomatic® II Ultrasonic Climate System Cleaner (VAS 6189B) and Airco-Clean® Ultrasonic Air Conditioning Treatment (VAS 6189/1).

1. Preparation: If the vehicle is equipped with an in-cabin pollen filter (common in A3, A6, and Q7 models), it must be removed, and its cover reinstalled before starting the treatment.
2. Vehicle Setup: Start the engine and adjust the climate control settings. This involves setting the temperature to its lowest, fan speed to its lowest, airflow direction to dash vents only, and activating both recirculation and ECON modes.
3. Treatment Application: A 100ml bottle of Airco-Clean® treatment is thoroughly shaken and poured into the Aircomatic® unit's filling chamber. The unit's outlet tube is then connected.
4. Positioning: The cleaning unit is placed in the passenger-side footwell, ensuring it is level. The power cord is routed through a slightly open window, while all other windows and the sunroof must be completely closed.
5. Cleaning Cycle: The unit is turned on, and the outlet tube is positioned to direct vapor into the recirculation air intake. The atomized cleaning fluid will be released from the vents. The treatment runs for 15-20 minutes, after which the machine automatically stops.
6. Multi-Zone Systems: For vehicles with a four-zone climate control system and two evaporators (such as the Q7 and A8), the procedure must be repeated for the rear A/C unit. The same A/C settings are used, and the outlet tube is positioned towards the fresh air inlet vent for the rear unit.
7. Post-Treatment: After the cleaning cycle, the vehicle should be aired out for approximately ten minutes. Technicians are also advised to check the Aircomatic® manual for unit maintenance instructions after each use.

Required Tools or Parts

To address the "2021 Audi e-tron musty A/C odor" as per TSB 2010146/15, specific tools and parts are required:

Part Number	Part Description	Quantity
VAS 6189/1	Airco-Clean® Ultrasonic Air Conditioning Treatment (100ml bottle)	1 bottle (for models with a single evaporator); 2 bottles (for models with two evaporators)
See ETKA	Fasteners, Bolts, Nuts, and Screws as needed per the Repair Manual	As needed

Tool Number	Tool Description
VAS 6189B	Aircomatic® II Ultrasonic Climate System Cleaning unit

Important Warnings

Owners should be aware of specific warranty conditions related to this TSB. This cleaning procedure is allowed only once per vehicle and must be performed within its first 12 months of service and under New Vehicle Limited Warranty (NVLW). There must be an original customer concern regarding the specified odor symptom on the repair order for this bulletin to apply; adding this procedure without a customer complaint is not permitted. If subsequent applications of the cleaning are necessary, they will be the customer's responsibility. Furthermore, replacement of the pollen filter under warranty is not allowed as part of this procedure; pollen filter coverage is only provided at the appropriate maintenance interval.

Owner Action

If your 2021 Audi e-tron exhibits an "unpleasant, musty odor coming from the heating and ventilation system," you should schedule an appointment with an authorized Audi service center. Inform them of the specific symptom you are experiencing. The service center will diagnose the issue and perform the cleaning procedure outlined in TSB 2010146/15 if applicable. Ensure your vehicle is within its first 12 months of service to qualify for warranty coverage of this procedure.

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NHTSA ID: 10174559