Coolant temp warning light

[2000986s]

My car just loves scaring the sh** out of me. Driving home from work tonight, the warning light on the temp gauge started flashing even through the arrow was pointing right down the middle. I pulled the car over, turned it off, waited a minute, and turned it back on. No flashing and drove home just fine. Any reason this would happen or was the ecu just playing a mean trick on me?

[JayG]

Check your coolant level

[2000986s]

Sorry should've added that: coolant levels are normal. I checked that right when I got home.

[911monty]

Four functions of the coolant warning light:

1. Engine coolant level too low
— light flashes slowly (0.5 Hz)
2. Engine compartment temperature too high
— light flashes slowly (0.5 Hz) (engine compartment blower might be faulty)
3. Engine coolant temperature too high
— light is lit; pointer on the right
4. Temperature sensor at water outlet faulty
— light flashes rapidly (1 Hz); pointer on the right

Note
The temperature warning in point three is indicated if the conditions "engine coolant temperature too high" and "engine coolant level too low" are present simultaneously
(1Hz = 1 flash per second. 0.5Hz = 2 seconds per flash)

[mikesz]

I have had similar problem. there is a sensor on the passenger side of the motor right on top of the engine easy and cheap replacement. I wound up changing that out then the engine bay cooling fan on the passenger side of the car.

[cas951]

Same issue happened to me but I did smell coolant briefly. I pulled over and looked around the trunk and under the car but I did not see any leaks. After about 5 minutes I restarted the car and the light never came back on.

When I got home I was a little low on coolant. Maybe 1/2 quart so I filled it to full level. Just for a precaution I replaced the coolant cap. The light never came back on. I even took the car on a 3000 miles road trip through Nevada and Utah desert and Colorado Pikes Peak. The light never came back.

[paulofto]

An old, loose or cross threaded coolant cap seems to be the biggest reason the flashing light occurs. Get the latest cap (.04), ensure the coolant is topped up, and screw the cap on straight and snug.

[2000986s]

Alright thank you all. I just had the car serviced less than a week ago, and coolant levels are normal. I will try the new coolant cap as a precautionary measure and hope that it's never an issue again.

Thanks again everyone!