The radiator fan can start running spontaneously.
The radiator fan is driven by the engine via a poly V-belt. The speed of the fan is varied by a viscous clutch according to the temperature.
There is also an auxiliary electric fan, which cuts in automatically whenever the temperature of the coolant and the engine compartment rises above a certain level.
The auxiliary fan can continue to run for as long as 10 minutes after stopping the engine – even after the ignition is switched off. It may also start running suddenly ⇒ after a while if
- • residual heat raises the coolant temperature, or
- • the hot engine compartment is additionally heated up by the sun.
When working in the engine compartment be aware that the radiator fan may start running suddenly – risk of injury.