Hybrid fans running constantly, is this correct?

[Brian R]

As the title suggests, the hybrid cooling fans run constantly in my LC500h, and I'm quite happy to accept that as a fact of life, assuming they are supposed to. However, I would normally expect any cooling fan to activate when the need arises. I'm also intrigued because last week I did quite a bit of motorway driving and again the fans ran constantly.

Just to let you know, I find it all but impossible to manually engage EV mode, but I can see and sense when it works in sympathy with the ICE.

Being new to hybrids I would welcome and be grateful for any observations from those more experienced with their idiosyncrasies.

 

 

[Spacewagon52]

53 minutes ago, Brian R said:

As the title suggests, the hybrid cooling fans run constantly in my LC500h, and I'm quite happy to accept that as a fact of life, assuming they are supposed to. However, I would normally expect any cooling fan to activate when the need arises. I'm also intrigued because last week I did quite a bit of motorway driving and again the fans ran constantly.

Just to let you know, I find it all but impossible to manually engage EV mode, but I can see and sense when it works in sympathy with the ICE.

Being new to hybrids I would welcome and be grateful for any observations from those more experienced with their idiosyncrasies.

 

 

Anything mentioned in the handbook Brian?

 A cracking car you have there. It has been quite warm lately so that may be a factor?

[Brian R]

1 minute ago, Spacewagon52 said:

Anything mentioned in the handbook Brian?

 A cracking car you have there. It has been quite warm lately so that may be a factor?

That's just the thing David, no mention of the fans operation (or at least I've yet to find anything) in the shall we say, rather extensive manual. I don't think I have heard them turn off since the day I bought it back in June. As I said, I'm not too fussed about it, but really just wanted to know if it's normal behaviour. Take your point about the weather but there have been early mornings when the outside temperatures have just clipped into single figures and still they run.

[dublet]

My RC300h is whisper quiet, and not noticed any cooling fans at all. Maybe we need to swap cars for a bit. 😉

I've got no problems getting mine into EV mode, but you do have to feather the throttle quite a lot as otherwise the engine kicks in.

[Brian R]

18 minutes ago, dublet said:

My RC300h is whisper quiet, and not noticed any cooling fans at all. Maybe we need to swap cars for a bit. 😉

I've got no problems getting mine into EV mode, but you do have to feather the throttle quite a lot as otherwise the engine kicks in.

Interesting and does make me wonder whether there is something amiss. Seems a bit more research is needed. As  for swapping cars then thank you for the suggestion and I will park that possibility for the time being. 😇 

[royoftherovers]

I`ll wager that your friendly Lexus Dealer knows....or will find out from Lexus .U.K. if he doesn`t., Brian 😉

[dublet]

10 minutes ago, Brian R said:

As  for swapping cars then thank you for the suggestion and I will park that possibility for the time being. 😇 

I only offer it as a matter of kindness, of course. To give you the experience of the wonderful RC 300h and the EV mode silent running. This kind of charity on my part is CBE worthy.

[dublet]

There's also some discussion about EV mode in this thread that you might find interesting:

 

[NemesisUK]

As dublet says, I've never heard the hybrid Battery cooling fans running now matter how hot it's been or how hard/fast I've driven. That's over 2 cars and 5yrs!

Are you sure it's a fan you hear? Do you have the ACS switched on, this can sound a little like a fan, at least in my RC, especially at 'idle'?

[Neo_gsf]

After having several Lexus Hybrids, you do have to adjust your driving style from normal petrol cars.  

For the EV mode, firstly you have to have at least 3 bars of Battery.  Secondly, as @dublet says, you have to feather the throttle - use the dashboard (or Head Up Display) to carefully only press the throttle enough to stay nicely within the "Eco" area.  Go anywhere near the "Power" area and you have too heavy a foot and it will instantly switch off the EV mode.  Lastly, if the car deems that it needs to have the Engine running to provide power for something then it will not allow you to engage EV mode.
In my 2021 RX, I can normally drive around 3 miles completely in EV mode before it goes down to 2 bars and the engine kicks in. 

[royoftherovers]

12 minutes ago, dublet said:

I only offer it as a matter of kindness, of course. To give you the experience of the wonderful RC 300h and the EV mode silent running. This kind of charity on my part is CBE worthy.

But Canvassing disqualifies, kind friend.🤣🤣🤣

[malcolmw]

This will probably sound a bit silly but the seat air conditioning fans on my LC run quite often and sound like cooling fans in the back of the car. If you have the Climate Concierge switched on and the internal temperature set low then these may well switch on automatically and sound like Battery cooling fans.

[NemesisUK]

^^^^^ I do hear this in my RC, if I have the seat ventilation on!

Great suggestion 👍

[dublet]

12 minutes ago, royoftherovers said:

But Canvassing disqualifies, kind friend.🤣🤣🤣

Sir Kind Friend, MBE, CBE, AA, RAC, GF, TLA, LOC to you.

[Brian R]

Many thanks for all the kind offers and suggestions as to what might be the "problem". Indeed, as Malcolm suggested, it was (notice past tense) the Climate Concierge system. Having turned it off, all is now as quiet as a graveyard. One "problem" solved, and now time to see if I can invoke stealth mode whilst training my right foot to moderate itself!

Thanks again gents, much appreciated help from the forum.

[wendle]

Interesting that when you turned the climate concierge off, the noise stopped, my question would be, why was the concierge system allowing the  heating / cooling fans to run ALL the time, not sure what settings you had, but once the temperature you have set is reached the concierge system should turn off and only come back on if the temperature in the car goes around 5 degrees  higher or lower than the temperature you have set, did you have it set on Auto.

[Brian R]

Hello Chris

Yes, it was on Auto and I've just got back from a tour of our local nurseries. For the first time I heard the climate control system kicking in and out as (I presume) setpoint temperature was reached. This would tend to suggest the Auto setting was over ridden and I seem to recall  Melissa from Northside Lexus showed a way to make part of the cooling system work contrary to what the settings might suggest. I'll see if I can find that presentation and if that explains the behaviour I have lived with for the last couple of months.

Needless to say I am grateful for a quieter cabin, albeit the noise was not that bothersome.

[cruisermark]

Glad this was not a fault and got sorted.

Whilst we are on the seat coolers subject, my son turned his side on in our LS430 - they were on for a few days and I could'nt figure out where the hissing sound was coming from untill finally I spotted that they have been switched on - trouble is these cars are so quite, every minute sound become a nuisance.

Lately I have been thinking more and more of replacing the front brake pads on mine because they make a groaning sound when coming to a stop.

[Alan305]

Same on our LS430, GS, IS and NX. If the seat cooler is on fan noise is present from the rear. Not certain it’s the Battery cooler. On the LS430 between the rear seats and the boot there was a complex of fans and trunking that chilled the car, front and rear seats and the drinks cabinet.

[lloydweb]

Late to this party, but I would have said the Climate Concierge running the seat cooler also! I wondered what this was a while ago and, when I realised, I turned Concierge off & never used it again. In hot weather, it just seems to dial everything up to 11.

[malcolmw]

I don't seem to have this issue with the Climate Concierge. Mine is always on and warms the seats on a cool day and ventilates them on hot ones. After fiddling about, I found that the default settings work pretty well. The fans speed up and slows down according to the excess temperatures detected. They don't come on all the time.

I have the climate control set to auto in all cases and the default set to Eco mode which seems perfectly sufficient in the UK.

[Brian R]

I think I found the video from Lexus Northside and as follows, in particular from 6 minutes onwards. 

Lexus Northside

[Superduner]

To check if the hybrid Battery cooling fans are working, get an obd dongle and use Hybrid Assistant on a mobile phone.  It will give you the Battery temperature and the level of cooling fan.

Mine is running at 39 degrees and level 3 (out of 6) when the outside temp is 30.  The fans take air from below the back seat, so, in theory, cold air from the air conditioning that collects on the floor.

[Brian R]

Curiously, just yesterday I had the car in for various reasons including a hybrid Battery re-check which the car failed on its most recent service in July. There was in reality a very good reason why it "failed" and in consequence I was asked to put 500 miles on it before a re-check could be initiated. This time around, it passed without incident and entirely as was suggested it would.

I believe/now know the constant fan I could hear from the back of the car was in reality nothing to do with the hybrid Battery fans, so all is now good. The video I linked as above does however provide some insight in how the ac might not be doing what you would expect and the simplest of workarounds.

Oh, and finally I got my maps updated by Lexus given when I tried to do the job there was a problem with the codes I was asked to enter.

Hopefully, I will not now see my local dealer till July next year.