If your engine temperature warning light is on, it means the engine is running hotter than it should. This is often a sign of overheating, which can cause serious damage if ignored. The issue may stem from low coolant, a failing water pump, radiator problems, or a faulty sensor. An assessment is needed immediately to identify and fix the cause.

What does it mean if the engine temperature warning light is on?

This warning light indicates that the engine’s cooling system cannot keep the engine within its safe temperature range. It may be caused by overheating, coolant leaks, or a malfunctioning cooling system component.

Common causes of the engine temperature warning light

• Low coolant level due to leaks
• Faulty thermostat stuck closed
• Failing water pump not circulating coolant
• Clogged or leaking radiator
• Cooling fan not engaging
• Head gasket failure allowing coolant loss
• Faulty temperature sensor or wiring

Why do you need to fix this problem quickly?

Overheating can cause major engine damage, including warped cylinder heads, blown head gaskets, and even complete engine failure. Immediate diagnosis and repair are essential to avoid costly repairs.

How do you know when to get it checked?

You should book an inspection if:

• The engine temperature light comes on or flashes
• The temperature gauge reads higher than normal
• Steam or smoke comes from under the bonnet
• You smell sweet coolant or burning from the engine bay
• The heater stops blowing warm air

What happens during an assessment?

A mechanic will:

1. Check coolant levels and top up if necessary
2. Inspect for leaks in the radiator, hoses, and water pump
3. Test the thermostat and cooling fan operation
4. Check the radiator and heater core for blockages
5. Inspect the head gasket for signs of failure
6. Scan the ECU for related fault codes

How much does it cost to fix?

Minor repairs such as topping up coolant or replacing a thermostat typically cost $150–$400. Larger repairs like water pump or radiator replacement range from $500–$1,200. Head gasket repairs can cost $1,500–$3,500+ if the issue is severe.

Is it unsafe to drive with the engine temperature warning light on?

Yes. Driving with an overheating engine can cause catastrophic engine damage. If the light comes on, you should safely pull over, switch off the engine, and arrange an inspection immediately.