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Energy saving airflow control. With S-Flow on, doesn't it detect passengers and direct air automatically? My wife has it on her 17RX, we never touch the control and it seems to work properly.
I dunno, does it? I drive about 80% with no passengers, 15% with a front seat passenger and 5% with one or two rear passengers and 1 front seat passenger. If I leave “S-Flow” ON, will it automatically know what to do?
Last edited by daryll40; Jul 14, 2020 at 11:47 AM.
OK, I found this video (below) that's pretty good. I think they are saying this:
S-Flow ON is a smart air-flow controller. It will send air to just the driver if there are no passengers. It will sense a front passenger and send the air to both the driver and front passenger, but no air to the back. What's not clear is what happens if there are rear passenger(s). Is there a sensor for that? If so, then S-Flow can stay "ON". If not, then it should be "CANCEL"ed so that air flows to the entire car, including to the rear passengers.
At least on my '18RX, opening and closing the rear door is enough to start sending air to the back seats. Resets when I shut down and lock the doors. I don't have the S-Flow dash button on mine.
While the S-Flow button is gone on my 2019 the S-Flow is still present. It was beastly hot the other day and I got into the car alone and noticed no air was coming from the rear vents. I picked up the kids and suddenly there was airflow back there - I'm guessing opening the rear door triggered it.
The fact is the entire volume of air within the cabin needs to be cooled for optimal comfort and when S-Flow is activated ⅔ of the cabin has reduced airflow. This is a "feature" I can't believe Lexus wasted a single $1 developing - the rationale from the start is flawed especially since I can't tell the difference in airflow in the front seat with S-Flow on or off - in other words it doesn't feel any colder or blow any harder when S-Flow is diverting airflow just to the front so now it's just restricting airflow to 2/3 of the car. Brilliant!
I want a job working for a car manufacture where engineers present stupid ideas like this and I just ask why and then smack them in the head.
What if the rear passengers get in BEFORE you start the car?
What if the rear passengers get in BEFORE you start the car?
Having the rear doors opened anytime after you unlock the doors (and yes, before the car is started too) will "disable" S-Flow and send air to the rear.
It's gotten to the point where if I know I want the air flow everywhere, I unlock the car, open the rear door (even if no one's going in), close the rear door, get in driver's seat, start the car and go.
Lexus should have made this a voice-activated command to toggle the S-Flow if they were going to add this (useless to me) feature and remove the dash button. Same with the A/C button.
Having the rear doors opened anytime after you unlock the doors (and yes, before the car is started too) will "disable" S-Flow and send air to the rear.
It's gotten to the point where if I know I want the air flow everywhere, I unlock the car, open the rear door (even if no one's going in), close the rear door, get in driver's seat, start the car and go.
Lexus should have made this a voice-activated command to toggle the S-Flow if they were going to add this (useless to me) feature and remove the dash button. Same with the A/C button.
OK, I found this video (below) that's pretty good. I think they are saying this:
S-Flow ON is a smart air-flow controller. It will send air to just the driver if there are no passengers. It will sense a front passenger and send the air to both the driver and front passenger, but no air to the back. What's not clear is what happens if there are rear passenger(s). Is there a sensor for that? If so, then S-Flow can stay "ON". If not, then it should be "CANCEL"ed so that air flows to the entire car, including to the rear passengers.
That's how I understand it, but it won't send cool air to the back, you have to press the button, it's easy sit someone in the back and if the green light of S-Flow is still on then it is not sending A/C to the back if it's off then it does. Also it doesn't work by only opening the back door as there many reasons to do that without a person sitting in those seats.
Having the rear doors opened anytime after you unlock the doors (and yes, before the car is started too) will "disable" S-Flow and send air to the rear.
It's gotten to the point where if I know I want the air flow everywhere, I unlock the car, open the rear door (even if no one's going in), close the rear door, get in driver's seat, start the car and go.
Lexus should have made this a voice-activated command to toggle the S-Flow if they were going to add this (useless to me) feature and remove the dash button. Same with the A/C button.
ONLY in 2018 MY and later, with my 2017 this doesn't work
OK, I guess I can't read or it doesn't work the way I think it should. From the RX350 manual:
Of course the Voice Commands doesn't have control of this feature.
What I want is to have the READ vents always working. I would 'think' that 'MANUAL' would do that?
What is happening is that the rear vents ONLY work when I open the Nav display, select Comfort, and then the Options menu, and I see this:
I only have #2 and it shows either a 'blue' or 'orange' bar. I assume BLUE is on, and when I turn it 'orange', I get airflow in the back. Even when no one is sitting there.
However, it now seems that this will not 'stick' between trips. I have to manually change it every trip. Is this normal? I don't think it was before, and the last time I was in the firmware for the Entertainment unit was updated.
So, is this 'normal' to have to set it each time, or do I have an issue with the car?
OK, so S-Flow will basically always be one. If I did set it to manual, it would revert to Auto on the next use of the car, correct?
All well and fine, but it doesn't allow airflow to the back seat it seems when someone is sitting in it? It says it will be disabled if a passenger is in a back seat, but that isn't happening? I have to manually disable it?
The explanation of S-flow in the manual is not Lexus' finest piece of prose. There's at least one other thread on this forum on the same subject. People who live in the hot parts, like Texas, really don't appreciate it.
RX350 Rear Seat AC/Heat controls, 2019 model
