What it means
This warning usually means the coolant level in the expansion reservoir is low. Amber generally means check soon, but colour, symbol, and alert behaviour vary by manufacturer; consult the owner's manual.
What the symbol looks like: A thermometer above wavy lines representing coolant, sometimes with a level mark.
Why it comes on
- Coolant leak from a hose, radiator, reservoir, or connection
- Coolant loss from a water pump or other cooling system fault
- Recent cooling system service or trapped air
- Faulty coolant level sensor or wiring
What to do
- Stop safely if the engine is hot or another temperature warning appears.
- Let the engine cool fully before checking the reservoir; do not open a hot pressurised cap.
- Check the coolant level and type specified in the owner's manual.
- If low, top up only as directed; if it leaks, is very low, or the warning persists, arrange inspection or recovery.
Can I keep driving?
If the engine temperature is normal and there is no visible leak, a short drive to a safe place or repairer may be possible after checking the manual. Stop if the temperature rises, steam appears, or coolant is leaking; avoid long trips.
Symbols and colours differ between makes and models. Your owner’s manual shows the exact lights of your car.