2025 Audi A5/S5 Driver Assist Fault U110100

Symptoms of Driver Assist Malfunctions

Owners of 2025 Audi A5 and S5 vehicles may experience various warning messages related to the driver assist systems. These messages indicate a malfunction in critical safety and convenience features. When diagnosed by a workshop, the system will log the diagnostic trouble code (DTC) U110100, often accompanied by the specific fault label "U110100: Component protection active, active/static, symptom: 1231633."

Fault Code Details

The primary fault code associated with this issue is U110100. This code signifies that component protection is active within the driver assist systems, specifically affecting short-range radars and adaptive cruise control units. The verbatim fault entry recorded in the vehicle's event memory is:

• "U110100: Component protection active, active/static, symptom: 1231633"

This DTC is typically logged in the event memories of the short-range radars (diagnostic addresses 8109, 810A, 810B, 810C) and/or the adaptive cruise control units (diagnostic addresses 0013, 008B). The presence of this Audi A5 U110100 fault indicates a system-wide issue rather than a failure of individual components.

The Underlying Cause

The root cause of these driver assist system malfunctions and the logged Audi A5 U110100 fault is a software issue within the Electronic Central Electrical (BCM) control unit J519 (diagnostic address 0009). This software defect prevents the component protection feature in the short-range radars from deactivating as it should. Component protection is a security measure designed to prevent unauthorized installation or swapping of control units. When it remains active in the short-range radars, it can lead to functional issues with various driver assist systems that rely on these components, resulting in the warning messages and the U110100 DTC.

Important Warnings for Owners

Audi Technical Service Bulletin 2078209/2 provides crucial information for owners and technicians regarding this issue:

• "Do not replace any components for this condition since this will not resolve the customer's concern." This is a critical warning, as replacing parts like short-range radars or adaptive cruise control units will not fix the underlying software problem in the BCM J519 and will result in unnecessary costs.
• "explain to the customer that a solution is expected to be available by the end of the 4th quarter of 2025 (subject to change) and that no repairs are necessary at this point." Owners should be aware that a permanent software update is in development and is anticipated to be released by the end of 2025. Until then, no permanent repair is required or available.
• "There is no reason to replace parts. If parts are replaced without good reason, they will be charged back." This reinforces the warning against premature parts replacement, indicating that such actions will not be covered under warranty.

This PSS (Pending Service Solution) may also apply to vehicles still within their new model launch repair authorization period. For such vehicles, workshops are instructed to create a TAC case and enter the vehicle into the PSS Database, referencing this TSB 2078209/2.

Temporary Resolution

While a permanent software solution is pending, a temporary measure can be performed in the workshop to clear the Audi A5 U110100 fault and temporarily resolve the driver assist system malfunctions. This involves performing a Terminal 30 reset of the Electronic Central Electrical (BCM) control unit J519. There are two options for this reset:

1. Fuse Removal: Identify all fuses for the BCM J519 using the current flow diagram and remove them for at least 10 minutes. This effectively power cycles the control unit.
2. Battery Disconnection: Disconnect the vehicle's 12V battery for a minimum of 10 minutes. This achieves a similar power cycle for the entire electrical system, including the BCM J519.

After either of these procedures, once the vehicle has completed a bus sleep cycle, the event memory can be deleted. This temporary measure can resolve the complaint, but the underlying software issue will likely cause the Audi A5 U110100 fault to reappear over time.

Warranty and Service Information

For warranty claims related to this issue, Audi specifies the following details under Transaction Number 2078209/2:

• Claim Type: If the vehicle is outside of any warranty, this Technical Service Bulletin is informational only.
• Service Number: 9710
• Damage Code: 0039
• Labor Operations:
  • GFF / Guided Functions (0150 0010): See SRT with associated operations.
  • GFF / Guided Functions (0150 0060): Time stated on the diagnostic protocol.
  • (Option 1) Repair Electronic Central Electrical (BCM) (9710 4199): 10 TU (Time Units).
  • (Option 2) Loosen and secure battery earth strap (9785 0950): See SRT with associated operations.
• Claim Comment: As per TSB 2078209/2.

All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual. It is crucial to remember that there is no reason to replace parts for this condition, and any parts replaced without valid reason will be charged back.

What Owners Should Know

If you own a 2025 Audi A5 or S5 and are experiencing "Various messages relating to driver assist systems malfunctions" or have had DTC U110100 diagnosed, it's important to understand that a permanent fix is being developed. Audi expects to release a solution by the end of the fourth quarter of 2025. In the interim, your dealer can perform a temporary Terminal 30 reset to clear the fault. Do not authorize the replacement of any components for this specific condition, as it will not resolve the underlying software issue and will likely not be covered under warranty. Dealers are instructed to create a PSS record for affected vehicles through the AccessAudi portal.

NHTSA ID: 11025382