C0400moderate severityChassis
Adaptive Cruise Control Sensor Alignment
on 2010 Audi R8 4.2L V8 · AWD
What this code means
The adaptive cruise control distance sensor is out of calibrated alignment.
Symptoms
- ACC unavailable message
- ACC warning light
- Cruise control not functioning
- Forward collision warning inactive
Common causes
- Sensor misaligned after collision
- Sensor bracket bent
- Windshield replacement shifted sensor
- Front fascia repair changed sensor aim
Diagnostic steps
- Perform ACC sensor alignment procedure
- Check sensor mounting bracket
- Inspect front fascia for damage or misalignment
- Verify sensor aim with manufacturer target and procedure
- Check for windshield-related codes if camera-based
Repair notes
Perform ACC sensor alignment using manufacturer-specified targets and procedure.
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