What Does the Traction Control Light Mean?

The traction control light (TC, TCS, or a car with squiggly lines) indicates that the traction control system has detected wheel slip and is actively intervening, or that the system has a fault and is disabled.

If the light flashes briefly during acceleration on a wet or loose surface, that's normal — the system is doing its job. If the light stays on continuously, the system has detected a fault and traction control is disabled.

Common Causes When the Light Stays On

Traction control shares many components with ABS, so faults often overlap:

• Faulty wheel speed sensor — The most common cause. Traction control relies on these sensors to detect wheel slip.
• Damaged sensor wiring — Exposed to road debris, salt, and water.
• Faulty steering angle sensor — Needs recalibration after wheel alignment or battery disconnect.
• ABS module fault — Traction control is managed by the ABS module.
• Low brake fluid — Triggers both ABS and traction control warnings.
• Aftermarket wheel/tyre size mismatch — Different rolling diameters confuse the speed sensors.

Is It Safe to Drive?

Yes, in most conditions. Your engine and brakes still work normally. Traction control primarily helps in:

• Wet or icy roads — prevents wheelspin during acceleration
• Loose gravel or dirt
• Hard acceleration from a standstill

Drive more carefully in poor conditions until the fault is repaired. Avoid aggressive acceleration from stops.

Related OBD-II Codes

Common traction control related codes:

• C0035-C0051 — Wheel Speed Sensor circuits
• C0455 — Steering Angle Sensor
• C0060-C0065 — ABS/TCS Motor circuits
• C0236 — Rear Wheel Speed Sensor Signal
• C0550 — ECU Internal Fault
• U0121 — Lost Communication With ABS Module

Repair Costs

Australian estimates:

• Wheel speed sensor: $120–$350
• Steering angle sensor recalibration: $80–$200
• ABS/TCS module: $400–$1200
• Wiring repair: $100–$300
• Steering angle sensor replacement: $200–$500