Technician A says an electric cooling fan may come on at any time without warning, even if the engine is not running. Technician B says an electric cooling fan may be controlled by the engine control computer. Who is correct?

Question

Quizplus · Accepted Answer

Both statements are correct. Electric cooling fans can indeed come on at any time, as they may be activated by the temperature of the engine coolant, not necessarily the engine running state. Additionally, modern vehicles often have their electric cooling fans controlled by the engine control computer (ECU/ECM), which decides when to turn the fan on or off based on various sensor inputs, including coolant temperature, air conditioning system pressure, and ambient temperature.

Technician a Says an Electric Cooling Fan May Come on at Any