2021-2023 Audi e-tron High Beam Assist / Traffic Sign Detection DTC C12B3FD

Symptoms

Owners of affected Audi vehicles, including the 2021-2023 Audi e-tron, may observe the following messages appearing in the instrument cluster, typically shortly after starting the vehicle:

• "High beam assist currently not available. Camera view restricted because of environmental factors."
• "Traffic sign detection: currently not available. Camera view restricted because of environmental factors."

Fault Codes / DTCs

For most affected vehicles, the front camera for driver assist systems control module (J1121, address word 00A5) may store a specific Diagnostic Trouble Code (DTC) when these symptoms occur. Note that for A3 models, a DTC may not be stored even if the message appears.

Code	Description	Symptom Code	Module
C12B3FD	Front camera for driver assist systems - temporary view restriction	221284	J1121 (DAS control module)

Technical Background

The front camera system relies on an unobstructed view to function correctly. If the camera detects a visibility restriction for more than 77 seconds, it will log the DTC C12B3FD with symptom code 221284. This DTC indicates a temporary view restriction. Once the visibility is restored, the message in the instrument cluster disappears, and the systems become sporadic.

To prevent visibility issues, a heating element is integrated under the cover of the front camera. This heating element activates automatically after the engine starts at low temperatures, when restricted visibility is detected, or when there's a risk of the glass fogging up.

Diagnosis / Trigger Conditions

The primary trigger for the "High beam assist currently not available" or "Traffic sign detection limited" messages and the Audi e-tron high beam assist C12B3FD fault is a temporary obstruction of the front camera's view. This can be due to fogging on the inside or outside of the windshield area where the camera is located. The system is designed to detect and react to these environmental factors.

Repair Procedure Summary

If you experience these messages or the Audi e-tron high beam assist C12B3FD, the following steps are recommended:

1. Understand Camera Heating: Familiarize yourself with how the camera's heating system works to maintain clear visibility.
2. Inspect Viewing Area: Visually inspect the front camera's viewing area on the windshield for any fogging or obstruction. This fogging can occur on both the inside and outside surfaces (as shown in Figures 1 and 2 of the original bulletin).
3. Activate Wipers: Often, simply activating the windshield wiper system can clear external obstructions or fogging, resolving the concern.
4. Internal Fogging Resolution: If internal fogging of the front camera's viewing area is a frequent issue, it may be necessary to remove the camera's lens hood to clean and dry the area thoroughly. This is a more involved procedure typically performed by a service technician.

Warranty Information

This Technical Service Bulletin outlines warranty coverage for the described condition. It is identified as TSB 96 22 77 2059201/5, superseding TSB 21-63 dated March 12, 2021. The current revision (Revision 5) added Model Year 2023 vehicles to the scope.

• Claim Type 110: Applies to vehicles up to 48 months or 50,000 miles.
• Claim Type G10: For Certified Pre-Owned (CPO) vehicles, ownership must be verified.
• If the vehicle is outside of any warranty coverage, this bulletin serves as informational guidance only.

The following codes are used for warranty claims:

• Service Number: 9638
• Damage Code: 0010
• Labor Operations:
  • Remove and install camera for assistance systems (lens hood): 9638 1999 (20 Time Units)
  • Clean and dry windscreen: 6410 2999 (10 Time Units)
  • Diagnostic Time (GFF): 0150 0000 (Time stated on diagnostic protocol, Max 25 Time Units)
  • Road test prior to service: 0121 0002 (0 Time Units)
  • Road test after service: 0121 0004 (0 Time Units)
• Claim Comment: As per TSB 2059201/4.

All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual and are subject to review by Audi Warranty.

Owner Action

If your Audi displays the "High beam assist currently not available" or "Traffic sign detection limited" messages, first try activating your windshield wipers to see if the issue resolves. If the problem persists or occurs frequently, especially with the Audi e-tron high beam assist C12B3FD code, it indicates a persistent visibility issue with the front camera. You should contact an authorized Audi service center to have the vehicle inspected. They can diagnose the exact cause, perform necessary cleaning, or address any underlying issues with the camera or its heating element.

Source: NHTSA ID 10210532