C0400moderate severityChassis
Adaptive Cruise Control Sensor Alignment
on 2021 BMW i3 42 kWh Single Motor RWD · RWD
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.
Other Chassis codes on this vehicle
C0021
LF Wheel Speed Sensor Range/Performance
C0022
RF Wheel Speed Sensor Range/Performance
C0023
LR Wheel Speed Sensor Range/Performance
C0024
RR Wheel Speed Sensor Range/Performance
C0025
LF Wheel Speed Sensor Circuit Intermittent
C0026
RF Wheel Speed Sensor Circuit Intermittent
C0027
LR Wheel Speed Sensor Circuit Intermittent
C0028
RR Wheel Speed Sensor Circuit Intermittent
C0035
Left Front Wheel Speed Sensor Circuit
C0036
Left Front Wheel Speed Signal Erratic