2021 Audi Driver Assist System Fault DTC C12B3FD

Audi has issued Technical Service Bulletin (TSB) 2059201/3 to address concerns regarding limited functionality of high beam assist and traffic sign detection systems in various 2021 Audi models. This TSB, which supersedes TSB 20-51, details the diagnostic and repair procedures for issues related to a restricted camera view.

Owners may notice warning messages appearing in the instrument cluster, particularly after starting the vehicle. These messages indicate that the driver assist systems are experiencing a temporary view restriction, often accompanied by the diagnostic trouble code (DTC) C12B3FD.

Symptoms

Owners of affected 2021 Audi vehicles may experience the following symptoms, typically appearing in the instrument cluster:

• "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."

These messages indicate that the front camera, which is crucial for these driver assist features, has a temporarily obstructed view.

Fault codes / DTCs

The primary diagnostic trouble code associated with this issue is:

This DTC C12B3FD is logged when the front camera detects a visibility restriction for more than 77 seconds. The message will disappear, and the systems will become available again once visibility is restored.

What the service bulletin says

The TSB explains that the front camera for driver assist systems (J1121 control module) has a heating element designed to prevent fogging. This heating element activates automatically at low temperatures or when restricted visibility is detected to ensure a clear camera view.

If a customer reports the issue, technicians are instructed to explain how the camera heating system works. They should also advise the customer to inspect the front camera's viewing area for fogging or obstruction, both inside and outside the vehicle. Often, activating the windshield wiper system can resolve external obstructions.

For persistent internal fogging, the bulletin suggests removing the camera's lens hood to clean and dry the viewing area. The TSB also provides specific labor operations and diagnostic times for these procedures under service number 9638, damage code 0010.

What to do

If you own a 2021 Audi and are experiencing the "High beam assist currently not available" or "Traffic sign detection limited" messages, or if you suspect an Audi e-tron C12B3FD issue, here's what you should do:

1. Check your front camera: Inspect the area around your vehicle's front camera (usually located near the rearview mirror) for any obstructions like dirt, ice, snow, or internal fogging.
2. Use your wipers: If the obstruction appears to be on the outside, try using your windshield wipers to clear the area.
3. Contact your Audi dealer: If the messages persist, or if you frequently encounter the Audi e-tron C12B3FD fault, it's best to schedule an appointment with an authorized Audi service center. They can diagnose the issue, perform necessary cleaning, or address any underlying problems with the camera or its heating element.

Source: NHTSA ID: 10176763