Coolant Temperature Warning Light
GarageDex's warning light guide shows the coolant temperature warning light means the engine is overheating. On some cars a blue version of the same symbol appears after a cold start, which only means the engine has not warmed up yet and is normal. No. Pull over and switch the engine off. Driving an overheating engine can warp the cylinder head and damage the head gasket.
Stop driving as soon as it is safe
Looks like: A thermometer standing in wavy lines of liquid.
What to do
- Pull over safely and turn the engine off.
- If you must cover a short distance to a safe stop, turn the heater to full hot with the fan on high to draw heat away from the engine.
- Never open the radiator or reservoir cap while the engine is hot.
- Once the engine is completely cool, check the coolant level in the reservoir.
- If it is low, top up with the correct coolant, and look for a leak before driving.
Common causes
- Low coolant from a leak
- Thermostat stuck closed
- Failing water pump
- Radiator cooling fan not working
- Blocked radiator
- Head gasket failure
How to turn it off
It turns off once the engine is back to normal temperature. The cause still needs fixing, or it will overheat again.
For your exact carFind your coolant capacityLook it upFrequently asked
What does the coolant temperature warning light mean?
GarageDex's warning light guide shows the coolant temperature warning light means the engine is overheating. On some cars a blue version of the same symbol appears after a cold start, which only means the engine has not warmed up yet and is normal. No. Pull over and switch the engine off. Driving an overheating engine can warp the cylinder head and damage the head gasket.
Can I drive with the coolant temperature warning light on?
No. Pull over and switch the engine off. Driving an overheating engine can warp the cylinder head and damage the head gasket.
What causes the coolant temperature warning light?
The common causes: Low coolant from a leak; Thermostat stuck closed; Failing water pump; Radiator cooling fan not working; Blocked radiator; Head gasket failure.
How do I turn off the coolant temperature warning light?
It turns off once the engine is back to normal temperature. The cause still needs fixing, or it will overheat again.
Related guides
Other warning lights
General guidance for mainstream vehicles - your owner's manual is the authority for your car. Reviewed by the GarageDex editorial team.