Climate control for middle row
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2022 GLS450
Climate control for middle row
I have a 6 passenger 2022 GLS450. I have noticed the air flow from the pillar vents and from the vents in contre console is poor. When I increase the speed or rear fans, I noticed the fan become louder but the air flow from front vents increase instead of rear vents.
My first MB ever - so not sure if this is normal?
My first MB ever - so not sure if this is normal?
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Joined: Sep 2019
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From: U.S.
Current/Last 5-years:GLS;G70;Alpina B8;X7;Accord. Sold:X7,TeslaS;S560;S550,X5;530e;L.Navigator;LS460
Make sure that the physical knob on each vent is also set to fully open.
The rolling knob on each of the rear vents is not a mechanical one. They have a sensor that will later adjust AC air flaps electronically to direct the distribution of flow through the air ducts. It's possible that these knobs are no longer sending a signal to adjust the air flaps. This is all separate from the AC fan speed.
Air flow fan speed is adjusting through the AC settings, but the flaps opening/closing % is electronically adjusted by those knobs on each of the vent. They look mechanical by they are not.
Air flow through 2nd and 3rd row AC vents is more than excellent. Much better than any other SUV I've seen.
The rolling knob on each of the rear vents is not a mechanical one. They have a sensor that will later adjust AC air flaps electronically to direct the distribution of flow through the air ducts. It's possible that these knobs are no longer sending a signal to adjust the air flaps. This is all separate from the AC fan speed.
Air flow fan speed is adjusting through the AC settings, but the flaps opening/closing % is electronically adjusted by those knobs on each of the vent. They look mechanical by they are not.
Air flow through 2nd and 3rd row AC vents is more than excellent. Much better than any other SUV I've seen.
Last edited by S_W222; Aug 31, 2025 at 03:59 PM.
MBWorld Fanatic!
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GLE 580
Make sure that the physical knob on each vent is also set to fully open.
The rolling knob on each of the rear vents is not a mechanical one. They have a sensor that will later adjust AC air flaps electronically to direct the distribution of flow through the air ducts. It's possible that these knobs are no longer sending a signal to adjust the air flaps. This is all separate from the AC fan speed.
Air flow fan speed is adjusting through the AC settings, but the flaps opening/closing % is electronically adjusted by those knobs on each of the vent. They look mechanical by they are not.
Air flow through 2nd and 3rd row AC vents is more than excellent. Much better than any other SUV I've seen.
The rolling knob on each of the rear vents is not a mechanical one. They have a sensor that will later adjust AC air flaps electronically to direct the distribution of flow through the air ducts. It's possible that these knobs are no longer sending a signal to adjust the air flaps. This is all separate from the AC fan speed.
Air flow fan speed is adjusting through the AC settings, but the flaps opening/closing % is electronically adjusted by those knobs on each of the vent. They look mechanical by they are not.
Air flow through 2nd and 3rd row AC vents is more than excellent. Much better than any other SUV I've seen.
