What it means
Traction control (TC or TCS) reduces wheel spin when you accelerate on slippery surfaces. The dashboard symbol is often a small car outline with squiggly or wavy lines beneath it — drivers search for it as the car with squiggly lines light or slippery-road symbol. When the light flashes briefly, the system is usually working. When it stays on steady, traction control may be switched off or a fault may be stored.
Flashing vs steady traction control light
A flashing traction control light during hard acceleration on wet, icy, or loose gravel usually means the system is cutting power to regain grip — that is normal. A steady amber light at startup that does not turn off often means TC is disabled (button pressed) or the stability system detected a fault. If the same drive also triggers the check engine light, scan engine codes first; an engine misfire or sensor fault can disable traction control on many vehicles.
What to do first
- Check whether you pressed the TC or ESC off button — some cars show a steady light when traction control is intentionally disabled.
- If the light flashed only on slippery pavement, ease off the throttle; no repair is needed if it clears.
- If the light stays on, note whether the check engine, ABS, or battery light is also on.
- Scan for fault codes if the steady light returns every drive — wheel speed sensors and steering-angle sensors are common causes.
Common causes of a steady light
- Traction or stability control switched off manually
- Faulty wheel speed sensor
- Steering angle or yaw sensor fault
- Engine misfire or emissions fault disabling stability aids
- Low battery voltage after a weak alternator or recent jump-start
- Blown fuse or control module communication fault
Traction control vs stability control (ESC/ESP)
Traction control limits drive-wheel spin during acceleration. Electronic stability control (ESC, ESP, or DSC on some brands) also helps correct skids by braking individual wheels. Many dashboards use similar car-with-lines icons; your owner's manual label may say TC, TCS, ESC, or ESP. A steady warning usually means the broader stability system needs attention, not just tire pressure or brakes alone.
Traction Control Light FAQ
What is the car with squiggly lines on the dashboard?
It is usually the traction control or stability control warning. The wavy or squiggly lines under a car outline mean the system is active, off, or has a fault related to wheel slip. Flashing on a wet road is often normal; steady amber after startup deserves a scan or button check.
Why is my traction control light on?
Most often the system was turned off, or a wheel speed sensor, steering sensor, or engine fault stored a code. Check the TC/ESC button first, then scan codes if the light stays on every trip.
Is it safe to drive with the traction control light on?
Usually yes if the car drives normally and no red warnings are on — but grip on wet or icy roads may be reduced if TC is disabled. Avoid hard acceleration and increase following distance until the system is checked.
Why did traction control and check engine light come on together?
An engine or transmission fault can disable traction control while the powertrain is in limp mode. Scan the check engine codes first; fixing the underlying engine fault often clears the TC light without a separate repair.
Does traction control affect the ABS light?
They share wheel speed sensors on many cars. A bad sensor can trigger ABS and traction warnings together, sometimes with a battery or steering light after low voltage. See our guide on two warning lights together if multiple icons are on.
Related symbols
Dashboard symbols vary by make and model. Always confirm the exact meaning in your owner's manual.