C0401
ACC Distance Sensor Circuit
2006-2011 BMW 328i 3.0L I6 🇩🇪
Moderate SeverityChassis
Description
General malfunction in the adaptive cruise control distance sensing radar or lidar unit.
Symptoms
- ACC system disabled
- Forward collision alert disabled
- Cruise control limited to non-adaptive mode
- Warning message on dash
Common Causes
- Radar/lidar unit failure
- Sensor blocked by dirt or ice
- Wiring damage to sensor
- Control module failure
Diagnostic Steps
- Clean sensor face (radar cover or camera lens)
- Check for obstructions in front of sensor
- Test sensor power supply
- Inspect wiring and connector
- Perform sensor self-test with scan tool
Repair Notes
Clean sensor area first. Replace radar/lidar unit if internal failure.
Related Codes
Other Chassis Codes
- C0021LF Wheel Speed Sensor Range/Performance
- C0022RF Wheel Speed Sensor Range/Performance
- C0023LR Wheel Speed Sensor Range/Performance
- C0024RR Wheel Speed Sensor Range/Performance
- C0025LF Wheel Speed Sensor Circuit Intermittent
- C0026RF Wheel Speed Sensor Circuit Intermittent
- C0027LR Wheel Speed Sensor Circuit Intermittent
- C0028RR Wheel Speed Sensor Circuit Intermittent
- C0035Left Front Wheel Speed Sensor Circuit
- C0036Left Front Wheel Speed Signal Erratic
C0401 on Other Vehicles
Common Questions
What does code C0401 mean on a 2006-2011 BMW 328i?
C0401 stands for "ACC Distance Sensor Circuit". General malfunction in the adaptive cruise control distance sensing radar or lidar unit.
What are the symptoms of C0401 on a BMW 328i?
Common symptoms of C0401 include: ACC system disabled, Forward collision alert disabled, Cruise control limited to non-adaptive mode, Warning message on dash.
What causes C0401 on a 2006-2011 BMW 328i?
Common causes of C0401 include: Radar/lidar unit failure, Sensor blocked by dirt or ice, Wiring damage to sensor, Control module failure.