Why does the 17 Mondeo engine fan keep running?

[DelPaislee]

The reasons why the Mondeo's electric fan keeps running are as follows: 1. Engine overheating caused by insufficient coolant, leading to continuous operation of the electric fan. 2. Engine overheating caused by radiator leakage, loose or damaged hoses causing water leakage, resulting in continuous operation of the electric fan. 3. Thermostat failure, due to which the temperature reaches the baseline but cannot send water to the radiator, or the water flow is insufficient, causing engine overheating and continuous operation of the electric fan. Thermostat failure, due to which the temperature reaches the baseline but cannot send water to the radiator, or the water flow is insufficient, causing engine overheating and continuous operation of the electric fan.

[HenryFitz]

My previous 2017 Mondeo had the same issue - the cooling fan just wouldn't stop spinning like it was on steroids. Don't rush to replace the entire fan assembly yet, as it's likely caused by other components. Pop the hood and feel the coolant hoses - if there's a significant temperature difference between the upper and lower hoses, the thermostat is probably stuck closed, preventing proper coolant circulation and forcing the fan to overwork. Also check if the radiator's exterior is clogged with cottonwood fluff - blocked fins will make the fan work overtime. By the way, there's a wiring harness connected to the electric fan's rear - try spraying some electrical contact cleaner on it. I once had a loose connector causing erratic fan behavior - it's a common issue with this model. If the fan spins even crazier when AC is on, check the AC pressure sensor - signal drift can really mess up the cooling system.

[DelAlivia]

The most dreaded scenario when driving a Mondeo in summer: the fan keeps whirring for five minutes after turning off the engine. Last time, I was utterly tormented until I discovered it was due to air trapped in the coolant. There's a twist-off cap at the top right corner of the radiator—remember to open it when the engine is cold and top up some antifreeze. The electronic fan controller is hidden in that black box behind the left headlight; this little thing is prone to acting up, and if it fails, the fan turns into a perpetual motion machine. It's crucial to have the repair shop scan for trouble codes with a computer. Last time, mine showed the coolant temperature sensor was giving false readings—replacing the sensor for 50 bucks fixed it instantly. When washing your car, always remember to rinse the front bumper's air intake grille clean. If the radiator fins are clogged with bugs or willow catkins, the fan will be working overtime every day.

[VonDeclan]

Be cautious about the fan spinning wildly. Last time, my temperature gauge needle almost hit the red line. The mechanic taught me a trick: after starting the engine, turn the AC to MAX, and the fan should have two-speed changes to be normal. If it only spins at high speed relentlessly, it's likely the low-speed relay is burnt. Open the inner liner of the left front wheel to find the fan module; the connector pins are prone to poor contact due to rust from rainwater. Remember to check the small metal box on the radiator frame; dual-fan cars have two sets of fuses. Once, I encountered a melted 20A fuse, causing the fan to lose control and become a perpetual motion machine.