2021 Audi A4 / S4 Tail Lamp Warning TSB

Owners of certain 2021 Audi A4 and S4 vehicles may experience an illuminated 'tail lamp warning' on their instrument cluster. This issue, detailed in NHTSA Manufacturer Communication 10204963, also notes that the warning may flash quicker after actuation, indicating a potential problem with the exterior lighting system.

This manufacturer communication highlights a software-related concern affecting the tail lights. The software update is designed to address the underlying causes of these warning messages and restore proper functionality to the tail lamp system.

Symptoms

Owners of affected 2021 Audi A4 or S4 models might notice a persistent 'tail lamp warning' appearing on their dashboard. Additionally, the warning light itself may exhibit unusual behavior, specifically flashing quicker than intended after the tail lamps are activated. These symptoms point to a software anomaly within the exterior lighting control system.

Fault Codes / DTCs

This bulletin indicates that the software update targets various diagnostic trouble codes (DTCs) related to the tail lamp warning. While specific DTCs are not detailed in the summary, the presence of these codes would trigger the 'tail lamp warning' and the associated rapid flashing. The software update aims to clear these underlying fault codes by correcting the system's logic.

Repair Procedure Summary

The resolution for the 'tail lamp warning' and the rapid flashing issue involves a software update. This update, as described in NHTSA Manufacturer Communication 10204963, will reprogram the relevant control module responsible for the exterior lighting system. The software correction is designed to eliminate the conditions that trigger the fault codes and the visible warning symptoms.

Owner Action

If you own a 2021 Audi A4 or S4 and are experiencing a 'tail lamp warning' or notice the warning flashing quicker after actuation, it is recommended to contact your authorized Audi dealership. They can confirm if your vehicle is covered by this manufacturer communication and perform the necessary software update. This repair is typically covered under warranty as a manufacturer communication addressing a known issue.

Source: NHTSA ID 10204963