C0405
Traction Control Active Too Long
TCS regulation has been continuously active longer than allowed, suggesting persistent low-friction conditions or a sensor fault.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: medium
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Common causes
Ordered by how often each turns out to be the cause.
- Persistent low-friction surfacePossible
- Wheel speed sensor driftPossible
Parts involved
- ABS Control Module
- Wheel Speed Sensors
C0405 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.