2021-2026 Audi Intersection/Lane Change Assist Inop TSB

Audi has issued Technical Service Bulletin (TSB) 2063336/4 to address instances where the intersection assist and lane change assist systems are inoperative. This condition is often accompanied by specific fault messages and the storage of DTC C12BFF0 in the vehicle's control modules.

This TSB provides comprehensive diagnostic and repair procedures for technicians to resolve these radar sensor-related issues, ensuring the proper functioning of crucial driver assistance systems in affected 2021-2026 Audi models.

Symptoms

Owners of affected Audi vehicles may observe one or more of the following symptoms, indicating an issue with the intersection or lane change assist systems:

• The intersection/lane change assist system is inoperative.
• The instrument cluster displays a message such as "Intersection assist: fault. Please contact workshop."
• A warning message like "Side assist and exit warning system: fault. Please contact workshop." appears.
• The message "Rear cross-traffic assist: fault. Please contact workshop." is shown.
• An "Audi pre sense: fault. Please contact workshop." warning may also be present.

Fault Codes / DTCs

When diagnosing this issue, technicians may find the following Diagnostic Trouble Code (DTC) stored in the lane change assist control modules (J769/J770) or the radar sensor control modules for object detection (J1088/J1089):

Technical Background / Diagnosis

The radar sensors responsible for intersection and lane change assist are designed to continuously calibrate themselves based on the vehicle's surroundings while driving above a certain speed. If the calculated dynamic angle offset of these sensors exceeds a threshold of +/-5° during this automatic calibration process, the system logs the Audi e-tron C12BFF0 DTC and triggers the corresponding fault messages in the instrument cluster.

This indicates a problem preventing the radar sensors from achieving or maintaining proper calibration, leading to the inoperative state of the assistance systems.

Repair Procedure Summary

Audi outlines a two-item repair procedure to address the Audi e-tron C12BFF0 and related inoperative assistance systems:

ITEM 1: Initial Sensor Check and Calibration

1. Technicians should first remove the corresponding radar sensor from its mount. This allows for inspection and ensures it is properly seated.
2. The sensor is then reseated securely in its mount.
3. After reseating, a calibration procedure is performed to attempt to re-establish proper sensor function.

ITEM 2: Sensor Swap and Full Replacement Procedure (if ITEM 1 fails)

1. If the calibration fails after performing ITEM 1, the left and right radar sensors are swapped.
2. Following the sensor swap, a full replacement procedure must be performed using the ODIS-S diagnostic system. This step is crucial to ensure the correct data set required for subsequent calibration is available on the sensors.
3. After successful activation through ODIS-S, another calibration procedure is performed.

Important Notice: Audi emphasizes that dynamic calibration is the preferred method for these sensors. Simply replacing a radar sensor without first identifying the root cause will likely not resolve the issue. The focus keyword Audi e-tron C12BFF0 highlights the core problem of calibration failure.

Owner Action

If your 2021-2026 Audi is displaying fault messages related to intersection assist, lane change assist, side assist, rear cross-traffic assist, or Audi pre sense, and you suspect an Audi e-tron C12BFF0 issue, it is recommended to schedule an appointment with an authorized Audi service center. They have the specialized tools, such as the ODIS-S system, and the training to accurately diagnose and perform the necessary calibration or repair procedures outlined in TSB 2063336/4. Warranty coverage for this repair will depend on your vehicle's warranty status at the time of service.