What it means
This warning indicates that the catalytic converter may be overheating or that its temperature has reached a level the vehicle considers unsafe. Red generally signals a serious condition that needs immediate attention, but the symbol and exact warning behaviour vary by manufacturer; check the owner's manual.
What the symbol looks like: A heat-shielded catalytic converter, often shown with heat waves beneath it.
Why it comes on
- An engine misfire sending unburned fuel into the exhaust
- A faulty oxygen sensor or air-fuel mixture problem
- A leaking fuel injector
- A restricted or damaged exhaust system
What to do
- Safely pull over as soon as you can.
- Switch off the engine and keep away from dry grass or other flammable material.
- Do not touch the exhaust or catalytic converter; they can stay extremely hot.
- Check the owner's manual and arrange professional diagnosis or recovery.
Can I keep driving?
Do not continue driving with this warning on, especially if the engine is misfiring, losing power, or the exhaust smells unusual. An overheating converter can become a fire risk and may be damaged further.
Symbols and colours differ between makes and models. Your owner’s manual shows the exact lights of your car.