Short answer
The frost or ice warning light, usually a snowflake, means the outside temperature is near or below freezing and the road may be icy. It is an advisory, not a fault. Slow down, leave more distance and brake gently, especially on bridges, overpasses and shaded stretches, which freeze before the rest of the road.
- Also shown as:
- Snowflake light · Ice warning · Low outside temperature warning
- What it looks like:
- A snowflake, often next to the outside temperature reading.
Is it safe to keep driving?
Yes, carefully. Bridges and shaded stretches ice first.
What causes the frost / ice warning light?
Most common first. Symbols and meanings vary by manufacturer; your owner's manual has the definitive meaning for your model.
- Outside temperature near freezing. The outside temperature sensor has dropped to the threshold the manufacturer chose, usually a few degrees above freezing; it varies by maker.
- Sensor placement. The sensor usually sits behind the front bumper, so it can read differently from the actual road surface, warmer in sun and cooler in shade.
What should you do right now?
- Slow down and leave more distance.
- Brake and steer gently, and watch for shiny patches of black ice.
- Nothing to fix — this is an advisory.
What does the fix usually involve?
No repair needed. If the temperature reading is clearly wrong, the outside temperature sensor behind the bumper may be damaged.
How much does it cost to fix?
Often nothing — see the causes above. The cost depends on what is actually wrong.
A typical range, not a quote. Actual cost depends on the car, the shop and the fault.
Common questions
Why does the snowflake light come on above freezing?
Many cars warn a few degrees above freezing, because the road surface can be colder than the air, especially on bridges and at night.
Does the ice warning mean the road is icy?
Not necessarily. It only knows the air temperature. Treat it as a reminder that ice is possible and drive accordingly.
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