2025-2026 Audi e-tron GT Yellow Electrical System Fault U019B00

Symptoms Owners May Notice

Owners of affected 2025-2026 Audi e-tron GT vehicles may experience specific issues related to an electrical system malfunction. The primary symptom is a "Yellow electrical system fault" displayed in the instrument cluster. This fault can lead to the vehicle being unable to start.

However, in many cases, the vehicle can be driven again after the ignition is switched off and then back on. This temporary resolution allows for continued use but does not address the underlying issue.

Fault Codes / DTCs

When diagnosing this condition, technicians will find specific Diagnostic Trouble Codes (DTCs) stored in the vehicle's control modules. The primary DTC associated with this issue is:

• U019B00 - Lost communication with Battery Charger Control Module

This DTC is typically stored in the Gateway control module, J533 (address word 0019). Additionally, other DTCs with titles such as "Lost communication with High-Voltage Battery Control Module" or similar messages may be logged in various other control units, indicating a broader communication loss within the electrical system.

Important Warnings for Owners

Audi has provided specific instructions to dealers regarding this condition, which are crucial for owners to understand:

• Do not replace any components for this condition, as doing so will not resolve the underlying issue. The problem is related to software, and hardware replacement is not an effective fix at this time.
• If your vehicle experiences the "Yellow electrical system fault" and cannot be started, please inform the customer that after switching the ignition off and on again, it will be possible to start the vehicle again. This provides a temporary workaround until a permanent solution is available.

Current Status and Solution

Audi is actively working on a software solution to address the Audi e-tron GT yellow electrical system fault. This solution is currently under development, and more information, including its availability, is not expected before the first quarter of 2025. The timeline is subject to change.

This Technical Service Bulletin, identified as 93 24 18 2075400/1 (also referenced as 2075400), serves to inform technicians about the issue and guide them on how to document it. There is no repair procedure available at this time, as the permanent fix is still being developed.

Owner Action

If your 2025-2026 Audi e-tron GT displays a "Yellow electrical system fault" or logs DTC U019B00, you should contact your authorized Audi dealer. While no immediate repair is available, your dealer can create a Pending Service Solutions (PSS) record to document your complaint. This helps Audi track the prevalence of the Audi e-tron GT yellow electrical system fault and ensures you are in line for the eventual software update.

Since no repairs are necessary at this point and replacing components will not resolve the issue, simply cycle your ignition if the vehicle fails to start. Audi will provide updates once the software solution is ready for deployment.

Warranty Information

This Technical Service Bulletin (TSB) is informational. For vehicles outside of warranty, this TSB is for informational purposes only. Warranty claims related to this issue should be processed according to Audi Warranty Policies and Procedures Manual, using Service Number 9352 and Damage Code 0039, with a claim comment referencing TSB 2075400/1.

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Source: NHTSA ID: 11009404