2023 Audi Q7 / SQ7 P275300 Transmission Fluid Cooler Hotfix

Symptoms

Owners of 2023 Audi Q7 and SQ7 vehicles may encounter a diagnostic issue where the P275300 Transmission Fluid Cooler Circuit/Open fault code is stored in the vehicle's system. The primary symptom for technicians is the absence of a relevant diagnostic test plan within the ODIS Service software to properly address this specific fault. This prevents effective diagnosis and repair of the underlying transmission fluid cooler circuit issue.

Fault Codes / DTCs

The specific diagnostic trouble code (DTC) addressed by this service information is:

• P275300: Transmission Fluid Cooler Circuit/Open

Diagnosis and Trigger Conditions

The issue arises when the P275300 Transmission Fluid Cooler Circuit/Open fault is present in a 2023 Audi Q7 or SQ7, but the Offboard Diagnostic Information System (ODIS Service) fails to populate the necessary diagnostic test plan. This prevents technicians from following the standard diagnostic procedure to troubleshoot and resolve the fault. The hotfix, identified as AOS-26-09, provides the missing test plan functionality.

Important Warnings for Technicians

Audi has issued critical warnings regarding the handling of this hotfix:

• "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 instructions emphasize that the hotfix is a temporary diagnostic tool and not a permanent software update for the vehicle. Improper management of the hotfix can lead to further diagnostic complications.

Repair Procedure Summary (for Technicians)

This Service Information (AOS-26-09) outlines the process for technicians to download, install, and uninstall a hotfix for the ODIS Service software. This hotfix is specifically designed to enable the correct diagnostic test plan for the P275300 Transmission Fluid Cooler Circuit/Open fault. The ODIS software version required for this hotfix is Audi brand version 2.40.3.

The procedure involves:

1. Downloading the Hotfix: Technicians must access AccessAudi.com via a web browser on their diagnostic device. They then navigate to Elsa2Go > Service References > Software/Hardware Updates and search for the "AOS-26-09 P275300 Transmission Fluid Cooler Circuit/Open Test Plan Hotfix Zip File." The file, identified by hotfix number A_2.40.3_N488_20260220-072237, is then downloaded and saved.
2. Installing the Hotfix: After downloading, the zip file is unzipped. The hotfix file is then copied to the desktop of the diagnostic computer. Technicians open ODIS Service (running as Administrator), expand the "Data" submenu, and click "Download" under "Hotfix." They then select the hotfix file from the desktop and confirm the import of the workshop data patch.
3. Performing Diagnostics: Once the hotfix is successfully installed, technicians can proceed with the diagnostic procedure for the P275300 fault, as the relevant test plan will now be available.
4. Uninstalling the Hotfix: Crucially, after completing the diagnostic procedure, the hotfix must be removed. Technicians must select "Erase" under "Hotfix" in the ODIS Service software and confirm the deletion of the active workshop patch. This step is vital to prevent malfunctions in future diagnostic sessions.

Owner Action

If you own a 2023 Audi Q7 or SQ7 and suspect an issue with your transmission fluid cooler, or if your vehicle's diagnostic scan reveals a P275300 Transmission Fluid Cooler Circuit/Open fault, it is recommended to contact your authorized Audi dealership. Inform them about the specific fault code. Your dealer's service department will have access to the necessary hotfix (AOS-26-09) to properly diagnose and address the issue using the Offboard Diagnostic Information System (ODIS Service).

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Source: NHTSA ID: 11029359