RX450H Gen 4 SFlow

chris_fletcher · January 22, 2018

Help

I have a gen 4 Fsport and sometime over the last month or so the sFlow seems to have stopped working correctly. The manual states the below. Howver the temperature display on the passenger side is always on even with recommended settings and no matter what s I change this is always the case. I had the car in for service at Lexus Leeds on Saturday and they initially advised thsi was normal and all SFlow does is to reduce the flow of air from the vents. On a test vehicle it did eventually turn off. Am I doing something wrong? I am taking it back nest week for the seat electric motors checking so if nobody has any bright ideas I will add this to the list

If a passenger is not detected in the front passenger seat, priority for the airflow
will be given to the driver's seat only.
In this case, the temperature indicator for the front passenger side will turn off.

rayaans · January 22, 2018

I was under the impression S-flow reduced the flow to the rear to heat the cabin up front quicker. Ive never noticed it turning off on the passenger side either. Unless its supposed to be in Auto, with efficient ventilation mode on and S-flow on as well and the DUAL setting turned off.

ChrisM · January 23, 2018

Looks like its time to RTFM ??

malcolmw · January 23, 2018

Yes, I agree that the S-Flow only seems to affect the rear airflow. I have noticed the passenger side temperature display go off sometimes but mostly it stays on. I don't think this is much to worry about.

chris_fletcher · January 23, 2018

3 hours ago, ChrisM said:

Looks like its time to RTFM ??

I have in fact read the manual and it states what I quoted in my original post.

"If a passenger is not detected in the front passenger seat, priority for the airflow
will be given to the driver's seat only.
In this case, the temperature indicator for the front passenger side will turn off. "

The engineer at Lexus theorised that the display only turns off when the vehicle reaches temperature. This actually happened this morning as outside temp was 10 degrees so car warmed up to that before I arrived at work and the display went off. Increasing the temp brought it back on.

Interestingly when cooling during summer the display was always off.

Re Rayaans response. Sflow controls rear and front prioritisation and no flow to rear if no passengers in the car but this is determined by opening of the rear doors which turns sflow off requiring manual reset

Ala Larj · January 23, 2018

9 minutes ago, chris_fletcher said:

Re Rayaans response. Sflow controls rear and front prioritisation and no flow to rear if no passengers in the car but this is determined by opening of the rear doors which turns sflow off requiring manual reset

Haven't tried this. Will need to check.

On mine as soon as I press the button the temp indicator on the passenger's side goes out if no one is sitting in the passenger seat regardless of outside and inside temps. In the rear nothing seems to change as I can stilll feeel air comniung out of the vents between the front seat.

I think the whole thing is a bit of a gimmick to be honest!

chris_fletcher · January 23, 2018

2 minutes ago, Ala Larj said:

Haven't tried this. Will need to check.

On mine as soon as I press the button the temp indicator on the passenger's side goes out if no one is sitting in the passenger seat regardless of outside and inside temps. In the rear nothing seems to change as I can stilll feeel air comniung out of the vents between the front seat.

I think the whole thing is a bit of a gimmick to be honest!

Try increasing the temperature and see if it comes on and then reduce and check it goes off. I did that this morning after noticing the display had turned off and increasing to 22 degrees it came back on then knocking it down to 20 turned it off. Clearly whilst the outside temp has been 3 degrees and below the interior is not reaching 20... never mind, mystery now solved

Ala Larj · January 23, 2018

I’ve just checked mine and no matter what I do the temp indicator on the passenger side stays off. The display also shows the back off but I can feel air coming through the vents! It doesn’t seem to make any difference if it’s on Auto or not. Also, opened the back door and it stayed off. Maybe mine’s got a fault!

See attached pics.

malcolmw · January 23, 2018

The OP was referring to the 4RX model. What happens on previous models is unknown to me.

Ala Larj · January 23, 2018

27 minutes ago, malcolmw said:

The OP was referring to the 4RX model. What happens on previous models is unknown to me.

Sorry was assuming they would all work in a similar way. And mine's not even an RX!

chris_fletcher · January 23, 2018

3 hours ago, Ala Larj said:

Sorry was assuming they would all work in a similar way. And mine's not even an RX!

But you have a fancy rear climate and 3 zone option too, makes me feel inadequate LOL

rayaans · January 24, 2018

21 hours ago, Ala Larj said:

I’ve just checked mine and no matter what I do the temp indicator on the passenger side stays off. The display also shows the back off but I can feel air coming through the vents! It doesn’t seem to make any difference if it’s on Auto or not. Also, opened the back door and it stayed off. Maybe mine’s got a fault!

See attached pics.

I think the GS one is controlled by the passengers sitting in the actual seats.

Ala Larj · January 24, 2018

1 minute ago, rayaans said:

I think the GS one is controlled by the passengers sitting in the actual seats.

Yes, I agree. If no passenger in in the seat the temp indicator never comes on. I assumed that all Lexuses fitted with this system would operate the same!

chris_fletcher · January 24, 2018

8 hours ago, Ala Larj said:

Yes, I agree. If no passenger in in the seat the temp indicator never comes on. I assumed that all Lexuses fitted with this system would operate the same!

Exactly what should happen in the RX but today it was back to its old tricks. Temp display would not go off, no matter what I adjsuted the temperature to using the controls. Only difference is todays outside temperature was 8 degrees vs 12 degrees yesterday. I am getting rather irritated now.

rayaans · January 24, 2018

3 minutes ago, chris_fletcher said:

Exactly what should happen in the RX but today it was back to its old tricks. Temp display would not go off, no matter what I adjsuted the temperature to using the controls. Only difference is todays outside temperature was 8 degrees vs 12 degrees yesterday. I am getting rather irritated now.

Was the car fully warm? Have you turned the efficient ventilation mode on in the settings?

TBH I wouldn't worry about it - having all vents running is better than just the drivers side.

Ala Larj · January 24, 2018

13 minutes ago, rayaans said:

Was the car fully warm? Have you turned the efficient ventilation mode on in the settings?

That's interesting. Mine is on but not really sure what it does. Will try again tomorrow with it off to see if it makes a difference. I really would expect all Lexus to operate in the same manner. Try that Chris, I'd be interested to know if it helps you.

chris_fletcher · January 24, 2018

2 hours ago, rayaans said:

Was the car fully warm? Have you turned the efficient ventilation mode on in the settings?

TBH I wouldn't worry about it - having all vents running is better than just the drivers side.

All settings the same as yesterday it just behaves differently. f its supposed to work then I expect it to and as its under warranty I will want it sorting (if its faulty) as later on the whole system might decide to go haywire :-)

Ala Larj · January 24, 2018

If it's under warranty I'd definitely get it sorted if it's not performing as per the manual.

chris_fletcher · January 24, 2018

1 hour ago, Ala Larj said:

That's interesting. Mine is on but not really sure what it does. Will try again tomorrow with it off to see if it makes a difference. I really would expect all Lexus to operate in the same manner. Try that Chris, I'd be interested to know if it helps you.

As per my reply to Rayaans. All settings the same today as yesterday and today temp display always on on passenger side. Stuff like this really winds me up LOL

Ala Larj · January 25, 2018

This is the limited information from my manual!

chris_fletcher · January 25, 2018

Manual says this

S-FLOW mode will be activated automatically according to the set temperature,

outside temperature, etc. (→P. 547)

However page 547 contains no information regarding outside temperature and sflow

malcolmw · January 25, 2018

My manual has the following on Page 545:

On Page 552 is this:

I agree with you that this is pretty vague.

rayaans · January 25, 2018

Figured out why mine never works then. I put my bag in the footwell behind my seat.

Ala Larj · January 25, 2018

7 minutes ago, rayaans said:

Figured out why mine never works then. I put my bag in the footwell behind my seat.

In my old IS my bag and four bottles of beer on the passenger seat were enough to set off the annoying 'fasten seat-belt bongs'. Fortunately the GS is not quite so senistive!

chris_fletcher · January 25, 2018

4 minutes ago, rayaans said:

Figured out why mine never works then. I put my bag in the footwell behind my seat.

But if the sflow light is on above the button then bag on floor behind the drivers seat should not make any difference and if you had opened the door after turning the car on then the light would be off. In any event it sounds like yours is behaving like mine or at least the temp display is always on??

I am going to raise it with Lexus Leeds next week to see if I can get a definitive answer as the instructions in the manual are both specific on how it should work but also vague on affecting factors. If current operation is normal fine but if not I will expect it fixing under warranty.