2024 Audi Q8 Warning Messages CAN Bus TSB 2075405/1

Owners of 2024 Audi models, including the Audi Q8, may encounter various warning messages displayed in the instrument cluster while driving, sometimes accompanied by the automatic lowering of side windows. This concern is detailed in Technical Service Bulletin (TSB) 2075405/1, which points to intermittent communication faults within the vehicle's CAN bus system.

Symptoms

Customers have reported a range of warning lamps appearing for different vehicle systems. These Audi Q8 warning messages can manifest as:

• "Vehicle lights: fault."
• "Emergency call function: fault."
• "Start/stop system: fault."
• "Stabilization control (ESC): fault."

These warnings are often intermittent and may coincide with the side windows lowering automatically. All functions typically restore themselves after approximately 30 seconds.

Fault Codes / DTCs

While no specific fault codes are consistently identified due to the varying nature of the issue, workshops have found that various intermittent Diagnostic Trouble Codes (DTCs) are stored. These DTCs are typically related to different bus systems and are logged in the Data Bus On Board Diagnostic Interface - J533- (address word 0019). The TSB indicates that these are often communication, single-wire, or signal faults.

Diagnosis and Trigger Conditions

The root cause of these Audi Q8 warning messages and related symptoms is an intermittent reset of the Data Bus On Board Diagnostic Interface - J533-. This reset can occur under certain conditions due to an Online Data Collector (ODC) campaign. Intermittent faults in both CAN and FlexRay communication are logged in various control units, all pointing to a temporary failure of the gateway J533.

To properly diagnose this issue, technicians must perform the following steps:

1. Read out the historical data in DA0019 using the Guided Fault Finding function under "Measured values."
2. Select and read the measured values for history data 78, 79, and 80, specifically for diagnostic address 0019.
3. Upload the collected LOG file containing the history data to GFF paperless.

Important Warnings for Owners and Technicians

Audi explicitly states a critical warning regarding this issue:

• Replacing the gateway J533 diagnostic address 0019 will not fix the issue, nor is it necessary. This means owners should not be upsold on a replacement J533 control unit, as it will not resolve the underlying problem.

Repair Procedure Summary

The long-term solution involves a software update. New software for the Data Bus On Board Diagnostic Interface - J533- (address word 0019) will be implemented in production vehicles as of week 25/2025 (model year 26). This update aims to prevent data collection campaigns from triggering the complaint again.

For current vehicles experiencing the Audi Q8 warning messages, the relevant data collection campaigns have been stopped as an immediate measure. If the concern occurs, all functions are typically restored after about 30 seconds. A temporary owner action to resolve the immediate concern is to turn terminal 15 off and then back on.

Warranty Information

This Technical Service Bulletin 2075405/1 provides guidelines for warranty claims. The service number associated with this bulletin is 9035, and the damage code is 0039. Labor operations for diagnosis using Guided Fault Finding (GFF) are specified as 0150 0010 and 0150 0060, with time allocated based on the diagnostic protocol. Warranty claims should be submitted according to the Audi Warranty Policies and Procedures Manual.

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Source: NHTSA ID: 11009383