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

Audi has released Technical Service Bulletin (TSB) 93 24 79 2074257/1 to address a specific issue affecting 2022-2024 Audi e-tron GT and RS e-tron GT vehicles. This bulletin provides guidance for technicians when owners experience a "red onboard supply warning" in the instrument cluster, often accompanied by a critical message. The core of the problem is a software-related fault that triggers a diagnostic trouble code (DTC).

This TSB is crucial for owners encountering the Audi e-tron GT P0B1300 fault, as it outlines the necessary diagnostic steps and the software update required to resolve the condition and restore proper vehicle operation.

Symptoms of the Audi e-tron GT P0B1300 Red Onboard Supply Fault

Owners of affected Audi e-tron GT and RS e-tron GT models may observe a prominent "red onboard supply warning" displayed in the instrument cluster. This warning is typically accompanied by a specific text message that reads: "Electrical system: fault. Safely stop vehicle". This message indicates a serious electrical system malfunction that requires immediate attention, prompting the driver to stop the vehicle for safety reasons.

Diagnostic Trouble Codes (DTCs)

When diagnosing this issue, technicians will find specific fault codes logged in the vehicle's diagnostic memory. In diagnostic address 008C (which pertains to hybrid battery management or BMC Software), the primary event memory entry is P0B1300. This DTC is described as "Hybrid/EV Battery Pack Current Sensor "A"/"B" Correlation". Additionally, a symptom number 1048614 is logged, indicating the specific nature of the correlation fault. This fault can be active/static or passive/intermittent.

Technical Background and Trigger Conditions

The root cause of the Audi e-tron GT P0B1300 fault is identified as a software issue within the Hybrid/EV Battery Pack Current Sensor system. This condition is specifically observed in vehicles where the BMC Software (diagnostic address 008C) is running one of the following versions: 1641, 1643, 1644, or 1645. Furthermore, the issue primarily affects vehicles with a production date (ZP8) prior to July 15, 2023.

Repair Procedure Summary

The resolution for the Audi e-tron GT P0B1300 red onboard supply fault involves performing a software update. Technicians are instructed to refer to TSB 2073768, titled "Combined software update Audi e-tron GT," for the detailed procedure. This update is designed to correct the underlying software anomaly that causes the Hybrid/EV Battery Pack Current Sensor correlation error and the associated warning messages.

Important Warnings and What Owners Should Know

Audi has noted that a software update will be made available at a later date for vehicles produced after July 15, 2023. When this update becomes available, TSB 93 24 79 2074257/1 will be updated accordingly. This means owners of vehicles produced after this date should be aware that their vehicle may require a different or subsequent update once it is released.

Warranty Information

For warranty claims related to this issue, the service number / damage code to be used is 9325 / 039. Technicians are advised to refer to TSB 2073768 for specific warranty accounting instructions when billing Audi AG or the importer. This ensures proper processing of the repair under warranty guidelines.

Source: NHTSA ID: 11005959