CC-ID-331low severityChassis
Hill Descent Control Active
on 2020 BMW M8 4.4L Twin-Turbo V8 · AWD
What this code means
Hill Descent Control is currently engaged and regulating vehicle speed during a descent. Raised by the stability control / HDC system via the instrument cluster.
Symptoms
- HDC active indicator illuminated
- Automatic brake modulation on descent
- Controlled descent speed maintained
Common causes
- HDC manually activated by driver
- Steep gradient detected
- Low-speed off-road driving
- System engaged as designed
Diagnostic steps
- Confirm HDC button engagement
- Verify normal HDC operation
- Check DSC module for related faults
- Scan for wheel speed sensor issues
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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