Promoe2005

Yesterday on the way home the buzzer in the dash went off, I wasn't at the red line, the add coolant light or the oil lights weren't on. I know the coolant and oil lights work. If I turned the wheel to the left it would stop but the moment I straightened it out the buzzing would start again. Just to be on the safe side I changed the oil and flushed the coolant system and made sure all the air was out of it. I cleaned and checked the sensor on top of the radiator as well. Any help would be very appreciated.