2025-2026 Audi Digital Key Cannot Delete TSB 2078471/4

Symptoms

Owners of certain 2025-2026 Audi models may experience a persistent "Connection offline" message, indicating a problem with their digital key functionality. The primary symptoms reported include being "Unable to delete a digital key in the vehicle or on the smartphone." Additionally, affected owners may find that "The digital key also does not work (cannot unlock/lock or start vehicle)" even when the vehicle is online, has sufficient satellite reception, and the ignition was not activated using the digital key.

Technical Background

According to Technical Service Bulletin (TSB) 2078471/4, the root cause of this Audi A6 digital key fault is identified as a software issue within the onboard supply control unit. This internal software malfunction prevents the proper management and deletion of digital keys, leading to the reported operational difficulties.

Diagnosis and Trigger Conditions

Before proceeding with any repair, technicians must first confirm several conditions. The vehicle needs to be online and have a valid time signal, along with sufficient satellite reception. It is also crucial to ensure that the ignition was not activated using a digital key. These preliminary checks are vital to accurately diagnose the Audi A6 digital key fault and ensure the subsequent repair steps are effective.

Repair Procedure Summary

Addressing the digital key deletion problem involves a series of diagnostic steps and potential software updates. If the digital key still cannot be deleted after these initial checks, the next step involves a 12V battery reset. This is performed by executing a Terminal 30 reset for a minimum of 10 minutes. Following the reset, it is imperative that the vehicle remains online for at least 24 hours, as the system will attempt to delete the key again during this period. Continuous online connectivity is essential for this process to succeed.

Should the issue persist, technicians are directed to check for the applicability of TSB 2079690, which details a "00 Combined software update 03.10.00/C (28.13.01) KD2". If this specific software update is available for the vehicle, it must be performed. A critical instruction to note is that any guidance within TSB 2079690 suggesting the digital key be deleted before the update must be disregarded. The digital key deletion process should only occur after the software update has been successfully completed, strictly following the subsequent instructions provided in TSB 2079690 for both deleting and re-creating the key user and the digital key itself.

Important Warnings

Owners and technicians should be aware of specific critical instructions related to this service bulletin. When performing the combined software update detailed in TSB 2079690, it is "imperative to precisely observe the instructions for deleting and creating the key user and digital key." Furthermore, if TSB 2079690 is performed, technicians must "ignore the instruction in the TSB that the digital key must be deleted before the update. Delete the key after the update and follow the subsequent instructions according to TSB 2079690."

Warranty Information

This Technical Service Bulletin (TSB) 2078471/4 outlines the warranty claim procedures for addressing the Audi A6 digital key fault. If the vehicle is outside of its warranty period, this bulletin serves as informational guidance only. The service number for this repair is 9710, and the associated damage code is KD02.

Applicable labor operations include:

• 0151 0010: Software update, including the necessary step of connecting a battery charger. This operation refers to the Service Repair Time (SRT) for associated operations.
• 0151 0040: This is a fixed rate for the comprehensive software update procedure. It covers all required preliminary and follow-up work, which includes managing the bus sleep cycle, performing a calibration drive, additional necessary work, and restarting the software update if flashing is aborted. This specific operation is allocated 130 Labor Time Units (TU).
• 9785 0999: This operation involves loosening and securing the earth strap, and it is allocated 20 Labor Time Units (TU).

All warranty claims must adhere to the guidelines set forth in the Audi Warranty Policies and Procedures Manual and are subject to review or audit by Audi Warranty. For combined software updates performed under warranty, time stamps are not required for billing, allowing for concurrent work on other vehicles and the involvement of non-productive personnel. The claim comment for this service should be specified as "As per TSB 2078471/4."

Revision History

Technical Service Bulletin 2078471/4 has undergone several revisions to ensure accuracy and completeness:

• Revision 4: The header was revised to include additional control modules, and the warranty section was updated with new labor operations.
• Revision 3 (November 10, 2025): The condition section was revised to include an updated model table. Service instructions and warranty labor operations were also updated.
• Revision 2 (July 3, 2025): Service instructions and warranty labor operations were revised.

Owner Action

If you own a 2025-2026 Audi A5, A6, Q5, S5, or SQ5 and are experiencing issues with your digital key, such as being unable to delete it or use it to unlock, lock, or start your vehicle, contact an authorized Audi service center. Inform them about the symptoms you are experiencing, specifically mentioning the Audi A6 digital key fault and TSB 2078471/4. The repair involves software updates and may be covered under your vehicle's warranty.

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Source: NHTSA ID 11027375