C0405low severityChassis
ACC Sensor Blocked
on 2013 Cadillac ATS 2.5L I4 · RWD
What this code means
The adaptive cruise control sensor reports its view is obstructed.
Symptoms
- ACC temporarily unavailable message
- Sensor blocked warning on dash
- ACC disengages in bad weather
Common causes
- Mud, snow, or ice covering sensor area
- Aftermarket grille or bumper cover blocking sensor
- Heavy rain or fog
- Damaged sensor cover or radome
Diagnostic steps
- Clean radar sensor cover or camera lens
- Inspect bumper fascia sensor opening
- Check for aftermarket parts blocking sensor
- Verify no damage to sensor radome
- Test in clear weather to confirm resolution
Repair notes
Clean sensor area thoroughly. Remove any aftermarket obstructions. Replace damaged radome.
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