2021-2024 Audi Phone Call Interference TSB 2065485/7

Audi Technical Service Bulletin 91 24 68 2065485/7, issued on October 16, 2024, addresses a specific concern for owners of certain Audi models: interference during phone calls that is synced to the engine's RPM. This technical service bulletin supersedes an earlier bulletin, Group 91 number 24-87, dated March 13, 2024. This issue, often manifesting as a whistling noise, affects the Bluetooth hands-free system in 2021-2024 Audi Q3, and 2022-2024 Audi A3, S3, and RS 3 vehicles. This article will detail the symptoms, the underlying cause, and the recommended repair for the Audi S3 phone call interference.

Symptoms

Owners of affected vehicles may experience the following symptoms related to Audi S3 phone call interference:

• When making a phone call via Bluetooth, the receiving person hears interference during the call.
• The interference is often described as a whistling noise that changes noticeably with the engine's RPM.
• The Speech Dialog System (SDS) may not be working correctly, although hands-free calls are still possible. Workshop findings confirm that this customer concern can be reproduced, and importantly, no relevant Diagnostic Trouble Codes (DTCs) are typically stored in the vehicle's system.

Important Warnings

Audi has issued specific warnings for technicians and owners regarding this issue:

• "Removing the connector from the OCU while the 12V battery is connected to the vehicle can result in permanent damage to the OCU." This highlights the need for proper service procedures.
• "Before applying this TSB, please make sure that the problem is reproducible, and that the interference noise is coupled to the engine RPM. Otherwise, this TSB does not apply, and repairs done according to this TSB may not resolve the customer concern." This is crucial for accurate diagnosis and ensuring the correct repair is performed.

Technical Background

The root cause of the Audi S3 phone call interference has been identified as a hardware issue within the Onboard Communications Unit (OCU), specifically the J949 control unit (address word 0075). A faulty power supply filter within this unit can cause engine RPM-related interference to be coupled into the microphone signal, leading to the reported whistling noise during Bluetooth calls. Audi implemented a production solution, identified as CW 38/24, to address this issue in newer vehicles.

Repair Procedure Summary

The repair procedure outlined in TSB 91 24 68 2065485/7 involves replacing the affected Onboard Communications Unit (OCU) J949. Here's a summary of the steps a technician will follow:

1. Disconnect Battery: The negative terminal of the vehicle's 12V battery must be disconnected to prevent damage during the repair.
2. Replace OCU: The emergency Onboard Communications Unit (OCU) -J949- is replaced. Technicians are instructed to follow the appropriate repair instructions found in the ELSA service information system for this component.
3. Reconnect Battery: After replacement, the negative terminal of the 12V battery is reconnected.
4. Run Test Plan: A part replacement test plan is run on the -J949- unit (diagnostic address 0075) to ensure proper functionality.
5. Verify Fix: Finally, the technician will check to confirm that the customer's concern regarding the phone call interference has been resolved.

Warranty Information

For vehicles still under warranty, this repair should be covered. The TSB specifies Service Number 9170 and Damage Code 0039 for warranty claims. Labor operations include "Remove and install/replace telematics control module" (9170 19XX or 9170 55XX), "Loosen and secure the negative 12V battery terminal connection" (9785 0999), "Charge Battery" (2706 8950), and "GFF" (0150 0060). If the vehicle is outside of its warranty period, this Technical Service Bulletin is for informational purposes only, and repair costs may be the owner's responsibility. All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual.

Owner Action

If you own a 2021-2024 Audi Q3, or a 2022-2024 Audi A3, S3, or RS 3 and are experiencing a whistling noise during Bluetooth phone calls that changes with engine RPM, you should contact your authorized Audi dealership. Describe the symptoms, specifically mentioning the engine RPM-synced whistling noise and any issues with the Speech Dialog System. Referencing Technical Service Bulletin 91 24 68 2065485/7 can help ensure your service advisor is aware of the known issue and the recommended repair. The dealership will be able to diagnose the Audi S3 phone call interference and perform the necessary Onboard Communications Unit (OCU) J949 replacement.

NHTSA ID: 11009962