It usually means your car’s cooling fan or radiator fan has stopped working, or is working poorly. That can lead to overheating, especially in traffic, at idle, or when the A/C is on.

What it can mean

A bad fan can be caused by a blown fuse, faulty relay, bad temperature sensor, wiring issue, or a worn fan motor.

Common signs

  • The temperature gauge rises when you’re stopped or moving slowly.
  • The A/C blows warm at a stop.
  • You may hear no fan noise, or the fan may run constantly.

What to do now

  1. Watch the temperature gauge closely.
  2. If it starts climbing fast, turn the heater to hot and the blower to high.
  3. Pull over safely if the gauge reaches hot or a warning light comes on.
  4. Avoid driving long distances until it’s checked, because overheating can damage the engine.

Simple example

If your car is fine on the highway but overheats in stop-and-go traffic, that often points to the cooling fan not kicking on when it should.

TL;DR: “Fan went out” in a car usually means the radiator/cooling fan failed, and the engine may overheat at low speeds or idle.