2025 Audi Q5 P049100 No Test Plan Hotfix AOS-25-34

Audi has issued a critical hotfix, identified as AOS-25-34, to address a diagnostic issue affecting 2025 Audi Q5 vehicles. This hotfix is specifically designed to provide a missing test plan for Diagnostic Trouble Code (DTC) P049100. Without this hotfix, technicians using the Offboard Diagnostic Information System Service (ODIS Service) would be unable to properly diagnose and repair vehicles presenting with this specific fault.

The hotfix, numbered A_2.38.3_DiagSetup_ECU0001_HF_20250616-092510, ensures that the ODIS software (Audi brand version 2.38.3) can correctly identify and guide the repair process for the P049100 fault. This update is crucial for accurate service and resolution of the underlying vehicle issue.

Symptoms

The primary symptom addressed by this hotfix is the presence of DTC P049100 in the Engine Control Module (ECM). This code is associated with the fault label "AIR System Insufficient Flow Bank active/static." Owners may not directly observe a specific dashboard warning for this, but it indicates an underlying issue with the vehicle's secondary air injection system.

Fault Codes / DTCs

The following Diagnostic Trouble Code is directly addressed by this hotfix:

Code	Description
P049100	AIR System Insufficient Flow Bank active/static

Important Warnings

Technicians performing this hotfix procedure must adhere to strict guidelines to prevent diagnostic system malfunctions. Audi explicitly states:

• "We recommend installation of this hotfix on one diagnostic device ONLY. Hotfix must be removed immediately after performing the procedure."
• "The Hotfix must be removed after performing the procedure. Failure to do so will cause other vehicle diagnostics sessions to malfunction."

These warnings highlight the temporary nature of the hotfix and the potential for adverse effects on other diagnostic tasks if not properly managed.

Repair Procedure Summary

The repair involves a multi-step process for Audi technicians to download, install, utilize, and then uninstall the hotfix from their ODIS diagnostic device. This ensures the correct diagnostic test plan for the Audi Q5 P049100 fault is temporarily available.

1. Download the Hotfix: Technicians must access AccessAudi.com via a web browser on the diagnostic device. They then navigate to Elsa2Go > Service References > Software/Hardware Updates and search for the AOS-25-34 Hotfix Zip File. This file is saved to the Windows desktop.
2. Install into ODIS Service: The downloaded hotfix file is copied to the desktop. Technicians open ODIS Service as an administrator, expand the 'Data' submenu, and select 'Download' under the 'Hotfix' section. They confirm the workshop data patch import and select the hotfix file from the desktop.
3. Perform Diagnostic Procedure: Once the hotfix is successfully imported, the technician can proceed with the diagnostic procedure for the 2025 Audi Q5 P049100 fault, which now has the necessary test plan.
4. Uninstall the Hotfix: Immediately after completing the diagnostic procedure, the hotfix must be uninstalled. This is done by selecting 'Erase' under the 'Hotfix' section in ODIS Service and confirming the deletion of the active workshop patch.

Required Tools or Parts

To apply this hotfix, technicians require an ODIS diagnostic device running Audi brand version 2.38.3 software. The hotfix file itself (A_2.38.3_DiagSetup_ECU0001_HF_20250616-092510) is downloaded from AccessAudi.com.

Owner Action

If you own a 2025 Audi Q5 and suspect an issue related to the secondary air injection system, or if your vehicle has presented with DTC P049100, you should contact your authorized Audi dealer. They are equipped with the necessary ODIS diagnostic tools and the AOS-25-34 hotfix to properly diagnose and resolve the "AIR System Insufficient Flow Bank active/static" condition.

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Source: NHTSA ID: 11020366