2025-2026 Audi e-tron Vehicle Cannot Lock or Unlock TSB

Owners of certain 2025-2026 Audi e-tron models may encounter a frustrating problem where their vehicle cannot be locked or unlocked using conventional methods. This issue, detailed in Technical Service Bulletin (TSB) 2078793/4, primarily affects vehicles equipped with a digital key and involves a software-related malfunction. The TSB, last revised on December 17, 2025, provides diagnostic information and a repair procedure to resolve the condition.

It's crucial for owners experiencing this problem to understand the symptoms, the underlying cause, and the recommended service steps. The core issue, identified as "57 Vehicle cannot be unlocked or locked", points to a system failure impacting the vehicle's access functions.

Revision History

Technical Service Bulletin 2078793/4 has undergone several revisions to refine its guidance:

• Revision 4 (December 17, 2025): This latest revision updated the header to include additional model years and revised the labor operations within the warranty section.
• Revision 3 (November 10, 2025): This revision provided an updated condition description, revised the model table and verbiage, added KD2 update instructions to the service section, and updated labor operations for warranty claims.
• Revision 2 (October 14, 2025): This earlier revision updated the service section with further information regarding the solution.

Symptoms of the Locking/Unlocking Issue

When the Audi e-tron vehicle cannot lock or unlock, owners typically observe several key symptoms. The primary complaint is the inability to lock or unlock the vehicle using any method, including the remote control key. When attempting to use the remote control key, the LED indicator on the key itself will not flash.

For Audi A5 and A6 e-tron models, the vehicle cannot be unlocked or locked using any method. For Audi Q5 and Q6 e-tron models, the vehicle can only be unlocked or locked via the door lock cylinder. In both cases, if an owner tries to lock the vehicle via the Audi app, they may see a specific error message: "Please switch off the ignition". This message can appear even when the ignition is already off, indicating a communication or system status discrepancy within the vehicle's digital key system.

Important Warnings for Owners

Audi has issued specific advisories regarding TSB 2078793/4 that owners should be aware of:

• Digital Key Requirement: "This TSB only applies if a key user has already been added for this vehicle and a digital key is being used." This means the bulletin is relevant only for vehicles where the digital key functionality is active.
• Remedy Condition: "This TSB only applies if the issue can be remedied using the procedure described in the customer statement. If in doubt, please check whether the issue was reproduced with the device on which the digital key is installed." This emphasizes that the TSB's solution is specific to the described symptoms and digital key usage.
• Starting Issues: "If the vehicle cannot be started after it is unlocked, please check whether there are any open field campaigns for the vehicle." This indicates that starting problems, if present, might be a separate issue requiring further investigation.

Diagnosis and Trigger Conditions

If your Audi e-tron vehicle cannot lock or unlock, there's an immediate measure that might temporarily restore functionality. If the device containing the digital key is moved outside the vehicle's range (approximately 132 feet) or its Bluetooth function is switched off, and about 15 minutes have passed without any activity (allowing the vehicle to enter deep bus sleep), the vehicle may then be unlocked and locked using the traditional remote control key. Once unlocked, the vehicle should be able to start without further issues.

The workshop findings confirm that the customer statement regarding the inability to lock or unlock the vehicle can be reproduced. There is no specific technical background or production solution noted for this condition, indicating it is primarily addressed through a service procedure.

Repair Procedure Summary

The primary solution for an Audi e-tron vehicle cannot lock or unlock due to this specific issue is a software update. If the customer's complaint can be resolved by following the initial diagnostic steps (such as the temporary measure described above), technicians are instructed to check for the availability of TSB 2079690. This TSB details the specific software update required, identified as "00 Combined software update 03.10.00/C (28.13.01) KD2".

If this specific software update is available for the affected vehicle, the procedure outlined in TSB 2076960 must be performed. A critical step in this repair process involves precisely observing the steps for deleting and then recreating the digital key both before and after the software update is applied. This ensures the digital key system is correctly re-initialized and synchronized with the new software. During the software update, it is essential to connect a battery charger to maintain stable voltage throughout the process.

Warranty and Service Information

For vehicles still under warranty, claims for this repair must adhere to the Audi Warranty Policies and Procedures Manual. The TSB specifies the following details for service and warranty claims:

• Claim Type: If the vehicle is outside of any warranty, this Technical Service Bulletin is informational only.
• Service Number: 9710
• Damage Code: KD02

Labor Operations:

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