2025 Audi A5/S5 Side Assist False Warnings TSB 2078803/2

Revision History

Technical Service Bulletin (TSB) 2078803/2 has undergone several updates since its initial release to refine the information and repair procedures:

• Revision 1 (July 31, 2025): This marks the initial publication of the TSB.
• Revision 2 (November 26, 2025): This update included revisions to the "Condition" section, specifically by adding a model table to clarify affected vehicles. Additionally, the "Service" section was revised to modify images, providing clearer visual guidance for the repair process.

Symptoms

Owners of 2025 Audi A5 and S5 vehicles may experience their side assist systems issuing warnings for no reason. This manifests as the "light in the exterior mirror on the corresponding side of the vehicle lights up" even when no other vehicle is present in the blind spot. This false 2025 Audi A5 side assist warning can be distracting and may lead to a loss of confidence in the vehicle's driver assistance features.

Diagnosis and Trigger Conditions

Audi's workshop findings indicate that the complaint of a false 2025 Audi A5 side assist warning can usually be reproduced during diagnostic checks. The technical background identifies the root cause as reflections occurring within the bumper carrier. These reflections interfere with the side assist sensors, leading to incorrect detection of objects in the blind spot, thereby triggering the warning light without an actual hazard.

Repair Procedure Summary

To address the false 2025 Audi A5 side assist warning, technicians will perform a service action detailed in TSB 2078803/2. The primary repair involves closing off specific openings on both sides of the bumper carrier. This is achieved using available caps or aluminum adhesive tape, depending on the vehicle's configuration.

The first step for technicians involves gaining access to the bumper carrier, which typically requires removing and then reinstalling the rear bumper cover. This labor operation is identified by code 6369 1900. Once the bumper carrier is accessible, the specific modification depends on whether the vehicle is equipped with a towing bracket.

• For vehicles equipped with a towing bracket: The openings on both the left and right sides of the bumper carrier are closed using a specific cap, part number 8B3.907.753.A. Image 1 in the TSB illustrates this, showing the left side of the bumper carrier with the cap installed, specifically for versions with a towing bracket.
• For vehicles without a towing bracket: The openings on the left side of the bumper carrier are closed using part number 8B3.907.753, and the openings on the right side use part number 8B3.907.754. Image 2 visually depicts the left side of the bumper carrier with the cap installed for versions without a towing bracket. Additionally, for these vehicles, technicians must also seal off any openings located on the top of the bumper carrier using commercially available aluminum adhesive tape. Image 3 provides a visual guide for this step, showing the left side of the bumper carrier's upper opening sealed with aluminum adhesive tape, again for versions without a towing bracket. This modification of the bumper carrier is covered under Labor Operation 6350 5099.

Required Tools or Parts

To correctly perform the repair for the 2025 Audi A5 side assist warning, technicians will need specific parts as detailed in TSB 2078803/2. The choice of parts depends on the vehicle's configuration regarding a towing bracket.

• For vehicles with a towing bracket:
  • Part number 8B3.907.753.A is required. This single part number is used for both the left and right sides of the bumper carrier to close the necessary openings.
• For vehicles without a towing bracket:
  • Part number 8B3.907.753 is required for the left side of the bumper carrier.
  • Part number 8B3.907.754 is required for the right side of the bumper carrier.
  • In addition to these caps, commercially available aluminum adhesive tape is also necessary. This tape is specifically used to seal off openings on the top of the bumper carrier for vehicles in this configuration, as illustrated in Image 3 of the bulletin.

Important Warnings

NOTICE: For 2025 Audi A5 and S5 vehicles without a towing bracket, it is crucial to also seal off the openings on the top of the bumper carrier. This requires the use of a commercially available aluminum adhesive tape, as illustrated in Image 3 of the service bulletin. Failure to do so may result in the false warnings persisting.

Warranty Information

The warranty claim process for addressing the 2025 Audi A5 side assist warning is detailed in TSB 2078803/2. If the vehicle is outside its warranty period, this Technical Service Bulletin serves as informational guidance only, and the repair costs would typically be borne by the owner. For vehicles still under warranty, the following claim details apply:

• Claim Type: If the vehicle is outside of any warranty, this Technical Service Bulletin is informational only. This implies that for in-warranty vehicles, the repair should be covered.
• Service Number: 9635
• Damage Code: 0010
• Labor Operations:
  • Remove and install rear bumper cover: This operation is identified by code 6369 1900. Technicians should refer to the Standard Repair Time (SRT) system for associated operations and precise time allocations.
  • Modify bumper carrier: This operation is identified by code 6350 5099. A standard time unit (TU) of 10 is allocated for this specific modification.
• Claim Comment: All warranty claims submitted for this issue should include the comment "As per TSB 2078803/2" to ensure proper processing.

All warranty claims must be submitted in strict accordance with the Audi Warranty Policies and Procedures Manual and are subject to review or audit by Audi Warranty.

What Owners Should Do

If you own a 2025 Audi A5 or S5 and are experiencing the described false 2025 Audi A5 side assist warning, where the light in your exterior mirror illuminates without a vehicle in your blind spot, it is recommended to contact your authorized Audi dealership. Inform them about the symptoms you are observing. While this is a Technical Service Bulletin and not a recall, it provides a specific repair procedure for a known issue. Your dealership can diagnose the problem and perform the necessary modifications to the bumper carrier as outlined in TSB 2078803/2. This repair involves sealing specific openings in the bumper carrier to prevent reflections from interfering with the side assist sensors. Since this is a TSB, the repair may be covered under warranty if your vehicle meets the eligibility criteria.

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Source: NHTSA ID 2078803/2