Kia Troubleshooting Questions? Ask a Mechanic
Does your car have a temperature gauge?
What colour is the thermometer symbol, blue or red?
Do you need any further help?
Hi there. Different expert here.
The thermometer symbol comes on when the temperature of the engine coolant exceeds the specification (click here for indicator symbols). If your Optima is still under the factory warranty, the best course of action is to turn off the engine to prevent further damage and then call Kia at 1-800-333-4KIA (4542) to arrange for repairs.