2022-2024 Audi e-tron GT P0B1300 Red Onboard Supply Fault

TSB Revision History

Technical Service Bulletin 2074257/2 was initially published on July 27, 2024. Revision 2, released on April 28, 2025, includes updated service instructions and revised warranty information, ensuring the most current procedures are followed for this issue.

Symptoms

Owners of 2022-2024 Audi e-tron GT vehicles may encounter a critical warning in the instrument cluster. The primary symptom is the illumination of a "red onboard supply fault" indicator, accompanied by the explicit message: "Electrical system: fault. Safely stop vehicle".

Beyond this direct warning, the condition can also manifest through various engine operation issues. These include the activation of malfunction display symbols, and the engine operation exhibiting a "no function" state during starting, while running, or when attempting to engage electro-drive mode. In some cases, the engine operation may be completely "stopped". These symptoms collectively point to a significant problem within the vehicle's electrical system, specifically related to the hybrid battery management.

Fault Codes / DTCs

When diagnosing the "red onboard supply fault" in an Audi e-tron GT, technicians will typically find specific diagnostic trouble codes (DTCs) stored in the vehicle's control units. The central DTC associated with this issue is P0B1300, which signifies a "Hybrid/EV Battery Pack Current Sensor 'A'/'B' Correlation" fault.

Diagnostic address	Diagnostic trouble code	Storage state
008C - Hybrid battery management	P0B1300: Hybrid/EV Battery Pack Current Sensor "A"/"B" Correlation	Intermittent
008C - Hybrid battery management	P0B1300: Hybrid/EV Battery Pack Current Sensor "A"/"B" Correlation	static

This DTC P0B1300 is specifically logged within the 008C - Hybrid battery management control unit and is often accompanied by symptom number 1048614, indicating the exact nature of the correlation fault. The fault can be recorded as either intermittent or static.

Diagnosis / Trigger Conditions

To accurately diagnose the Audi e-tron GT P0B1300 fault, a technician will first confirm the customer's complaint by reproducing the "Electrical system: fault. Safely stop vehicle" message in the instrument cluster. The next crucial step involves accessing the diagnostic address 008C, which pertains to the Hybrid battery management system, to check for stored event memories.

The presence of DTC P0B1300, particularly with symptom number 1048614, logged as either active/static or passive/intermittent, confirms the issue. Furthermore, the Technical Service Bulletin 2074257/2 specifies that affected vehicles will have a software version for the BMC (008C – hybrid battery management) that is one of the following: 1641, 1643, 1644, or 1645. Verifying these software versions is a key indicator for this particular Audi e-tron GT P0B1300 fault.

Repair Procedure Summary

Audi Technical Service Bulletin 2074257/2 identifies the root cause of the "red onboard supply fault" and DTC P0B1300 as a software issue within the hybrid battery management system. The repair does not involve replacing any hardware components but rather requires a software update.

To resolve this Audi e-tron GT P0B1300 fault, authorized Audi service centers are instructed to perform service campaign 91VT. This campaign involves updating the software for the 008C - Hybrid battery management control unit to correct the correlation problem with the Hybrid/EV Battery Pack Current Sensor. This is a specific software calibration designed to address the underlying technical background of the issue.

Warranty Information

Owners should be aware that the repair for this condition, performed under service campaign 91VT, is covered under warranty. Service centers are instructed to refer to the specific accounting instructions for service campaign 91VT when processing the warranty claim for this software update.

Important Warnings

Audi has stated that there is no "Production Solution" applicable for this issue, meaning it is not a factory-level fix for new vehicles but rather a service action to be performed on affected vehicles already in the field. All part and service references provided in this TSB (2074257) are subject to change and/or removal, so technicians must always check with their Parts Department and/or ETKA for the latest information and parts bulletins. Furthermore, the Repair Manual should be consulted for any fasteners, bolts, nuts, and screws that require replacement during the repair process.

Owner Action

If your 2022-2024 Audi e-tron GT displays a "red onboard supply fault" or the message "Electrical system: fault. Safely stop vehicle", or if you suspect your vehicle is affected by the Audi e-tron GT P0B1300 fault, you should contact an authorized Audi service center. They will be able to diagnose the issue and perform the necessary software update under service campaign 91VT, which is covered by warranty.

NHTSA ID: 11017676