2023-2024 Audi e-tron, Q8 e-tron DC Charging Fails (U15AF00)

Owners of 2023-2024 Audi e-tron and Q8 e-tron models may encounter issues with DC fast charging, particularly when the Plug & Charge function is activated. This technical service bulletin (TSB) 93 23 26 2071345/1, issued on September 8, 2023, addresses instances where DC charging does not start or fails, often accompanied by the Diagnostic Trouble Code (DTC) U15AF00.

This TSB clarifies that the problem is generally not with the vehicle itself but rather with the software of the charging station being used. It provides important guidance for both owners and technicians on how to identify and manage this condition without unnecessary vehicle repairs. This bulletin specifically applies if the vehicle's Plug & Charge function is activated and the workshop findings described below are met.

Symptoms

Owners may observe the following conditions indicating a problem with DC charging when Plug & Charge is active:

• DC charging does not start. The vehicle fails to initiate a charging session at a DC fast charging station.
• LED on charging socket pulsates in white. This visual cue indicates an attempted but unsuccessful charging connection.
• The charging complaint can be reproduced repeatedly at the same specific charging station.
• AC charging works without any issues, suggesting the problem is specific to DC charging or the Plug & Charge feature.

When a technician inspects the vehicle, they will typically find that the vehicle's Plug & Charge function is activated. Furthermore, the Control Module for High-voltage battery charger (J1050, address word 00C6) will store a specific Diagnostic Trouble Code.

Fault Codes / DTCs

The primary diagnostic trouble code associated with this issue is:

| Code | Description | Module | | :--- | :---------- | | U15AF00 | Fast battery charging (DC) Charging station encoding failed with symptom 2097297 (passive/intermittent) | Control Module for High-voltage battery charger (J1050) |

This DTC, U15AF00, directly points to a communication or encoding failure during the DC fast charging process, specifically when the Plug & Charge protocol is in use.

Diagnosis / Trigger Conditions

The root cause of this Audi e-tron U15AF00 issue lies in the compatibility between the vehicle's Plug & Charge function and the charging station's software. Some DC charging stations claim to be compatible with vehicles using Plug & Charge, but not all have received the necessary software updates to enable this function reliably. This means that the charging station may not start the charging process when the Plug & Charge function is switched on in the vehicle.

This discrepancy means that some charging stations may not properly initiate the charging process when the vehicle's Plug & Charge feature is active. The problem is often consistently reproducible at the same affected charging station, while AC charging remains unaffected.

Important Warnings

Audi has issued critical advisories regarding this specific Audi e-tron U15AF00 issue:

• Do not replace parts: Parts replacement will not resolve this issue. Claims for replaced parts will be subject to review, indicating that such repairs are unnecessary and will not be covered under warranty if performed for this specific condition.
• Not a vehicle fault: This is not a fault with the vehicle itself. The issue is caused by the software of the charging station not having been updated to properly support the Plug & Charge function.

Owner Action

If you experience DC charging issues with your 2023-2024 Audi e-tron or Q8 e-tron when Plug & Charge is active, the immediate solution is straightforward:

• Disable Plug & Charge: As soon as the Plug & Charge function is switched off in your vehicle's settings, charging at the affected DC charging stations should be possible again without issues. This allows you to continue using the charging station for DC fast charging, albeit without the automatic Plug & Charge feature.
• Try another charging station: If possible, try a different DC fast charging station that may have updated software to support Plug & Charge.

This TSB is informational only and is not applicable to any Audi Warranty claims for repairs related to this condition, as it is not considered a vehicle defect. All part and service references provided in this TSB (2071345) are subject to change and/or removal, so always check with your Parts Department for the latest information.

NHTSA ID: 2071345