What causes the red coolant temperature warning light to come on in a sedan?

[DelBella]

On the dashboard, there is a coolant temperature light. When the engine is cold, a green coolant temperature light illuminates, which disappears as the temperature rises. When the temperature is too high or there is insufficient coolant, a red coolant temperature warning light will illuminate to alert the driver, and the vehicle should be stopped immediately for inspection. Common fault points include: 1. Insufficient antifreeze in the engine cooling system: Possible leaks in the engine, such as water pump leakage, pipe damage, radiator damage, etc. 2. Thermostat malfunction: Leading to excessively high coolant temperature. Because the thermostat fails to open, the flow of coolant within the engine is obstructed, causing the coolant temperature to rise too high. 3. Cooling fan malfunction: Resulting in poor heat dissipation of the coolant. Thus, the coolant temperature light comes on, indicating excessively high coolant temperature. 4. Water pump malfunction: The water pump does not rotate smoothly, leading to poor coolant circulation, which triggers the coolant temperature light and causes the coolant temperature to become too high.