SL/R230: Vent blower speed
Thread Starter
Senior Member
Joined: Mar 2008
Posts: 326
Likes: 27
From: Southeast PA
2024 911 Turbo S, 2023 Denali 2500 HD, 2026 G63
Vent blower speed
I just bought a used 2008 SL550 and I noticed that when I leave all the climate controls on auto the vent blower always runs right at the middle speed. When the car warms up and gets to the desired temp the blower does not decrease. Even on a warm 50 degree day the blower always runs at medium. It just seems loud when running at mid speed. I have had many cars with auto climate and once the temp gets where it is set the blower speed goes down to low. My wifes 2007 ML350 goes right down to low speed once the temp is reached and you can hardly hear it blowing. Just wondering if this is normal for a SL or I need to take it in to the dealer and have it looked at.
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Joined: Aug 2004
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From: Tallahassee, Florida
2006 SL600, 2001 S500, 1996 SL320
Does Not Sound Normal
Does not sound normal to me, fan speed on auto should change as needed to control dialed in temperature. I would have it checked out.
Thread Starter
Senior Member
Joined: Mar 2008
Posts: 326
Likes: 27
From: Southeast PA
2024 911 Turbo S, 2023 Denali 2500 HD, 2026 G63
I thought so. You know how dealers tell you that things are normal and you do not know what to believe so I just wanted to get some opinions before I had taken it in for them to look at it. How many light bars come on yours once the desired temp is reached?
Thread Starter
Senior Member
Joined: Mar 2008
Posts: 326
Likes: 27
From: Southeast PA
2024 911 Turbo S, 2023 Denali 2500 HD, 2026 G63
Update
I had my wife take the car to the dealer yesterday to have them look at the climate control. They plugged it in and no codes came up so they updated the software and they claimed that solved the problem. When I got home last night I checked it out and now none of the lights come on when in auto mode. Before the software update the light bar would tell you how high the fan was blowing. It is no better with the new software. Sitting in my garage last night at 60 degrees the fan was still running very high even when the inside temp reached the setting. It was equivalent to manual mode with 4 light bars which is medium speed. I do not believe that this can be normal. This car is so quite inside that all I can hear is the fan blower. 
Can anyone else detail on your climate control.
Can anyone else detail on your climate control.
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Joined: Feb 2009
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From: Central WI (BFE)
SL55, ML500 & Acura TL
I had my wife take the car to the dealer yesterday to have them look at the climate control. They plugged it in and no codes came up so they updated the software and they claimed that solved the problem. When I got home last night I checked it out and now none of the lights come on when in auto mode. Before the software update the light bar would tell you how high the fan was blowing. It is no better with the new software. Sitting in my garage last night at 60 degrees the fan was still running very high even when the inside temp reached the setting. It was equivalent to manual mode with 4 light bars which is medium speed. I do not believe that this can be normal. This car is so quite inside that all I can hear is the fan blower. Can anyone else detail on your climate control.
Can anyone else detail on your climate control.Trending Topics
Thread Starter
Senior Member
Joined: Mar 2008
Posts: 326
Likes: 27
From: Southeast PA
2024 911 Turbo S, 2023 Denali 2500 HD, 2026 G63
I am taking it back this week so they can look at it again. There is no way that it can be right. I was out yesterday for a long drive and the outside temp was 55 degrees. When left in auto it was equivalent to 4 bars which is about medium speed. I pushed the bottom off on the auto and adjusted it down to low and it still kept the inside at the comfortable temperature. It is annoying to hear the fan running so high.
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MBWorld Fanatic!
Joined: Feb 2009
Posts: 6,897
Likes: 85
From: Central WI (BFE)
SL55, ML500 & Acura TL
I am taking it back this week so they can look at it again. There is no way that it can be right. I was out yesterday for a long drive and the outside temp was 55 degrees. When left in auto it was equivalent to 4 bars which is about medium speed. I pushed the bottom off on the auto and adjusted it down to low and it still kept the inside at the comfortable temperature. It is annoying to hear the fan running so high.
