Active Grill Shutter aka Louvers - how do they work??

[PNBLWZD]

Chatterbot to the rescue!

Those are active grille shutters.

They’re motorized flaps in front of the radiator that open and close automatically, and their purpose is mainly:
1. Aerodynamics & Fuel Efficiency – When the engine doesn’t need maximum cooling (like at highway cruise), the shutters stay closed to reduce drag and improve MPG.
2. Engine Warm-Up – Closed shutters help the engine reach operating temperature faster, especially in cold weather, which improves efficiency and emissions.
3. Cooling On Demand – When the engine, transmission, or A/C system needs extra cooling, the shutters open to let more air through the radiator and intercooler.
4. Noise Reduction – By reducing airflow turbulence, they can also cut down wind noise at speed.

On the new Broncos, Ford uses them mostly for efficiency and emissions compliance, while still giving the cooling system all the airflow it needs when off-road or under load.

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[ThunderFlash]

Who uses their AC when the temp is 65 degrees????

I think you just saved me a lot of unnecessary hassle! I've had my doors and top off for the last 5 months. I noticed my '22 WT seemed to be running warm. I was worried some combo of the ADD bumper, winch, 7" lights, bash plate, full SFR skids plates, added weight, and/or FP tune were interfering with air flow and run warmer than it should be. I was regularly hitting 225°F on hills or hard acceleration and would really need to baby it on flats to get below 200°F. I knew it had been running 180-190°F in the past. Even if those aren't catastrophic temps, it's harder on the oil and thermal cycles do no good for most things, particularly plastics. Being topless/doorless, why the heck run the A/C....just a waste and more parasitic load on the motor.

Just did a little test drive and sure as snot, the louvers were behaving as you described. It was typically running about 185°F and would only approach 200°F on bigger hills with the A/C active. I was in the process of making a plan to rearrange my front end to try to improve the cooling air flow, maybe even add a heavy duty radiator. I still might make air flow improvements, but at least now I know what's up with some of the temp spikes. Thanks for posting that.

 

[Cholla_Magnet]

I know that the lower shutters close in Eco mode for aerodynamic reasons, are they opening and closing other modes? I am typically in a very hot region so I was considering disconnecting the lower actuator so that the lower shutters were open all the time and I could still run in Eco mode for the shifting point/gas mileage boost. Are the lower shutters closed in Eco mode even when it's hot? I maybe could reconnect when it got cold again.

 

[Ducati1098]

I know that the lower shutters close in Eco mode for aerodynamic reasons, are they opening and closing other modes? I am typically in a very hot region so I was considering disconnecting the lower actuator so that the lower shutters were open all the time and I could still run in Eco mode for the shifting point/gas mileage boost. Are the lower shutters closed in Eco mode even when it's hot? I maybe could reconnect when it got cold again.

If you disconnect the motor, I’m pretty sure the vehicle will go into limp mode and you’ll have no boost whatsoever. So that’s not really an option.

Edit: nevermind, I was wrong

 

[Brian_B]

If you disconnect the motor, I’m pretty sure the vehicle will go into limp mode and you’ll have no boost whatsoever. So that’s not really an option.

Does it really go that far and not just throw a DTC? wow. I know a lot of folks yanked theirs out for high-n-tight winches or aftermarket radiators (and were keeping the motors plugged in to avoid the code), but didn't know it would send it into limp mode.

I know that the lower shutters close in Eco mode for aerodynamic reasons, are they opening and closing other modes? I am typically in a very hot region so I was considering disconnecting the lower actuator so that the lower shutters were open all the time and I could still run in Eco mode for the shifting point/gas mileage boost. Are the lower shutters closed in Eco mode even when it's hot? I maybe could reconnect when it got cold again.

To kinda sorta answer your question - the shutters do default to closing in Eco mode, but it won't overheat your engine or anything. You're safe to run Eco mode all you want no matter what temp it is. The shutters just cover the intercooler (which only cools the intake air), there's still plenty of uncovered area for the radiator and transmission cooler and what not. If the intake air gets too warm, the engine will detune and make less power, but that's kinda what Eco mode is supposed to do anyway.

Many people remove the shutters (but keep the motor plugged in, so the computer thinks it's still doing something)

 

[Fordified1]

If you disconnect the motor, I’m pretty sure the vehicle will go into limp mode and you’ll have no boost whatsoever. So that’s not really an option.

I took my intercooler shutter thingy completely out when I changed front bumpers over 2 years ago and no codes, seat of the pants runs the same. The plug is just hanging there.
2024 2.3 automatic. Stock, no tune.

 

[Ducati1098]

Does it really go that far and not just throw a DTC? wow. I know a lot of folks yanked theirs out for high-n-tight winches or aftermarket radiators (and were keeping the motors plugged in to avoid the code), but didn't know it would send it into limp mode.

I took my intercooler shutter thingy completely out when I changed front bumpers over 2 years ago and no codes, seat of the pants runs the same. The plug is just hanging there.
2024 2.3 automatic. Stock, no tune.

Oh okay nevermind then. For some reason I thought I remembered seeing a recent post of someone that had a lower shutter issue and it put it into limp mode, but maybe I misunderstood. Or maybe it was because it got stuck closed? I’m not sure.

 

[Fordified1]

Oh okay nevermind then. For some reason I thought I remembered seeing a recent post of someone that had a lower shutter issue and it put it into limp mode, but maybe I misunderstood. Or maybe it was because it got stuck closed? I’m not sure.

Maybe Ford changed how it’s programmed?

 

[Brian_B]

i honestly don’t know one way or the other to be honest

 

[Ducati1098]

Maybe Ford changed how it’s programmed?

Yeah possible I suppose

 

[Fordified1]

Yeah possible I suppose

On the subject of auto software updates, sent you a PM.

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