Adaptive Suspension 18' RCF

[Jgtcracer]

All,

Very much enjoying the RCF but do have a question regarding the AVS active suspension on the car.  I'm very much struggling to notice a difference to suspension firmness, irrespective of drive mode.  Should it be quite noticeable?  My only real experience of active suspension comes from my FK8 civic but its quite noticeable between the 3 modes.  Having done a bit of research it seems that many mention that it does make quite a difference on the RCF but I'm struggling to notice with the ride being very firm all the time.  Ive checked tyre pressures and all around 35psi.

I did notice a few threads mentioning that the AVS can sometimes need resetting, is this indeed true and if so is it just a disconnect the Battery job?

Appreciate the responses in advance.

Marcus

[B1RMA]

It should be very noticeable, as I've mentioned before I tried two cars more or less back to back. Although the AVS car was £12K more I bought it.

On any given road drive down it in Sports and just note the ride, then put it in Sports + and you should notice the much firmer ride.

I can appreciate that I went from a AMG CL65 with the fully active suspension system but I can assure you there should, and is a difference.

Just double check that under the bonnet you have an electric wire running out at the top of the strut, if not return the car under the sale of goods act, if you have the wires do the test.

I thought that when I put 20 inch wheels on my car it may ruin the ride but under normal settings it's fine.

For the record I always drive my car in Sports with paddle change and never in Sports+ because the suspension system is 'smart' it tightens up noticeable when you get a shift on so no need for the bone shaking Sports +

[NemesisUK]

Just the 'lowly' 300h RC for me but the AVS is very noticeable in the different modes. Much more so than my previous MB CLS55 on AIRmatic.

I tend to use Normal around town/urban driving. The suspension tightens nicely on fast roundabouts etc.. but is nice and compliant on the less than smooth roads. Also I don't need the accentuated throttle response in traffic, nor the tightened steering response one gets in the Sport/Sport+ modes.

On the open roads it's Sport mode all the way! Sports+ if I want to 'play' but it's really too firm for normal driving on roads round here, mid corner bumps really upsets the handling.

As David suggests, double check you actually have AVS, I thought it was optional on the '18 model year?

[B1RMA]

Just to add I've never had to re-set mine, even when the car completely died due to an uncharged Battery, when charged everything was normal.

[Jgtcracer]

3 hours ago, B1RMA said:

It should be very noticeable, as I've mentioned before I tried two cars more or less back to back. Although the AVS car was £12K more I bought it.

On any given road drive down it in Sports and just note the ride, then put it in Sports + and you should notice the much firmer ride.

I can appreciate that I went from a AMG CL65 with the fully active suspension system but I can assure you there should, and is a difference.

Just double check that under the bonnet you have an electric wire running out at the top of the strut, if not return the car under the sale of goods act, if you have the wires do the test.

I thought that when I put 20 inch wheels on my car it may ruin the ride but under normal settings it's fine.

For the record I always drive my car in Sports with paddle change and never in Sports+ because the suspension system is 'smart' it tightens up noticeable when you get a shift on so no need for the bone shaking Sports +

All, thanks very much for the responses.  It has got AVS, checked and can see that the wiring is indeed there.  I wonder whether I need to just pop it into a Lexus dealer then.  It’s tough as I don’t know what it ‘should’ be like so it’s hard to know if something is wrong!

 I’m certainly struggling to notice any difference between all the modes and it sounds like I should.

Marcus

[B1RMA]

44 minutes ago, Jgtcracer said:

All, thanks very much for the responses.  It has got AVS, checked and can see that the wiring is indeed there.  I wonder whether I need to just pop it into a Lexus dealer then.  It’s tough as I don’t know what it ‘should’ be like so it’s hard to know if something is wrong!

 I’m certainly struggling to notice any difference between all the modes and it sounds like I should.

Marcus

Well at least you have peace of mind that the car does indeed have AVS.

I'm guessing that the display gives you the read-out/graphic that  you have engaged AVS.

Best find a bit of road preferably a B road i.e. typical British B road being a bit rough then drive down it in normal then do it again in the various driving modes.

There should be a significant difference in the Sport+ mode which is why I never use it, having said that I chose the car because under normal driving modes including Sport it was just so smooth, good luck.

Personally I have found the dealers to be very polite, that's about all regarding technical stuff.

[Jgtcracer]

Readout that I have engaged AVS?? Can’t see a mention of it in the manual.

 

I’ll have a closer look when I’m home but didn’t realise I have to switch it on.

[B1RMA]

17 minutes ago, Jgtcracer said:

Readout that I have engaged AVS?? Can’t see a mention of it in the manual.

 

I’ll have a closer look when I’m home but didn’t realise I have to switch it on.

Sorry didn't explain that too well, you don't switch it on the drive mode display should indicate that the suspension has altered as well as other items.

[Jgtcracer]

I’ll have a better look when I’m home and see if I can find the visualisation.  

Much appreciated

[Arnett]

7 hours ago, B1RMA said:

Just double check that under the bonnet you have an electric wire running out at the top of the strut, if not return the car under the sale of goods act, if you have the wires do the test.

 

Consumer rights act *

 

But pretty sure he also purchased it over the phone so would fall under distant selling act  🎉 14 days to return if unhappy pow pow. 

[Rompy]

Just to add my view. My 17 RCF carbon has AVS and I’m sure it doesn’t do anything. Steering is more precise in S+, but I can’t detect any other changes to suspension. My previous C63s used to noticeably tense up (or go hench) when going into S+, but the RCF just doesn’t. Maybe the change is too subtle for me. By the way, we’ve owned the RCF three years this week. No other car has lasted more than a year in the last two decades. So that’s quite a feat for us. 

[Jgtcracer]

7 hours ago, Rompy said:

Just to add my view. My 17 RCF carbon has AVS and I’m sure it doesn’t do anything. Steering is more precise in S+, but I can’t detect any other changes to suspension. My previous C63s used to noticeably tense up (or go hench) when going into S+, but the RCF just doesn’t. Maybe the change is too subtle for me. By the way, we’ve owned the RCF three years this week. No other car has lasted more than a year in the last two decades. So that’s quite a feat for us. 

Thanks for the reply.  Had a little more time with the car and still not convinced that it changes much but if I try very hard I may notice a slight difference between sport + and everything else.  Tend to drive in normal   Also think I’m starting to get used to it which probably helps.  I can’t imagine Lexus fitted it if it isn’t doing anything but I do struggle to perceive the difference.
 

I would never have thought that my civic would be softer than the Lexus though!

[B1RMA]

Interesting comment about the AVS. As I mentioned I did a back to back test of a car with and without. Not sure whether it was my last car that had the ultimate in AMG active ride control that perhaps made me focus on the ride more. At the time I had a client Donington Park Raceway and was travelling up in the AMG fairly regularly and from Portsmouth it was a fair drive. So the RCF was a hard act to follow.

I can on any given day just ride down any road and notice the difference between Sport S and Sport S+. My thoughts were that in Sports S+ it was a little stiffer than a standard RCF without. I did think I may have ruined this by fitting 20 inch wheels but it hasn't.

[Jgtcracer]

All, thought I would resurrect this thread rather than hijack another.  Seems that stiff suspension on AVS cars has been known to happen, please see link below.

 Thoughts?
 

https://www.clublexus.com/forums/rc-f-2015-present/935039-anyone-had-this-suspension-issue.html

[ColinBarber]

As stated near the bottom of that thread with the procedure, Lexus only require an initialisation if the suspension ECU is replaced. But I guess it wouldn't hurt to try - but you do need Techstream.

[Jgtcracer]

7 minutes ago, ColinBarber said:

As stated near the bottom of that thread with the procedure, Lexus only require an initialisation if the suspension ECU is replaced. But I guess it wouldn't hurt to try - but you do need Techstream.

I’ll ask them to look into it when it’s in on the 5th.

[B1RMA]

I'm glad you have resurrected this thread, as I mentioned originally my AMG had that wonderful air suspension system that ensured the car always rode flat.

It also was a real magic carpet ride and on a long distance journey certainly made the drive very enjoyable. The reason I said this was because I replaced the AMG with the RCF.

On my test drive of the AVS equipped car I concluded that it obviously wasn't as good as the AMG but it was so close.

Perhaps my many years of owning powerful Luxo Barges made me oversensitive to ride quality I don't know.

But I would never of bought the non AVS car.

It's a shame you are so far away as I'd welcome you to drive mine even with its 20 inch wheels.

You need to find someone who knows their onions to check it out because I'm sure there must be something not right. 

[NemesisUK]

Mmmm.. I found the AVS on my RC300h was far superior to the AIRmatic on my CLS55. The AMG was very compliant and but did dip and lean far more than the RC, which was totally flat under cornering and braking. But then there was 16yrs between the two cars..

I find the drive modes in the Lexus (both the RC and now the RX) far more differentiated than those in the Merc, it was difficult to differentiate the modes in the AMG but then it was a far more performance oriented model..

[Jgtcracer]

I lived in Gosport/Fareham for years so may have worked out!  Definitely something going on with the car, will be interesting to see how Newcastle deal with it and whether they are willing to engage with me or just try and fob me off

[B1RMA]

13 hours ago, Jgtcracer said:

All, thought I would resurrect this thread rather than hijack another.  Seems that stiff suspension on AVS cars has been known to happen, please see link below.

 Thoughts?
 

https://www.clublexus.com/forums/rc-f-2015-present/935039-anyone-had-this-suspension-issue.html

This looks to be the answer doesn't it. Perhaps it just needs to be re-set, in fact it seems obvious.

[B1RMA]

On 4/26/2022 at 10:06 AM, NemesisUK said:

Just the 'lowly' 300h RC for me but the AVS is very noticeable in the different modes. Much more so than my previous MB CLS55 on AIRmatic.

I tend to use Normal around town/urban driving. The suspension tightens nicely on fast roundabouts etc.. but is nice and compliant on the less than smooth roads. Also I don't need the accentuated throttle response in traffic, nor the tightened steering response one gets in the Sport/Sport+ modes.

On the open roads it's Sport mode all the way! Sports+ if I want to 'play' but it's really too firm for normal driving on roads round here, mid corner bumps really upsets the handling.

As David suggests, double check you actually have AVS, I thought it was optional on the '18 model year?

I wonder if the suspension system in the CL65 AMG could have been different. I know I had a conversation on Pistonheads with a chap praising the CL65 suspension system because even with it's pretty hefty 600 plus BHP it never changed it's super flat appearance under heavy acceleration or braking. Also it's cornering prowess for a big car was pretty tidy on A roads. Just a thought because it was super comfy regardless of how it was driven, although I like the N/A V8 in the RCF part of me misses a twin turbo V12.

[B1RMA]

were the connections removed when you changed the springs?

[Jgtcracer]

7 hours ago, B1RMA said:

were the connections removed when you changed the springs?

Yea, though I’m not  convinced it was working even before I fitted them.  Certainly no difference before/after install.  I’m going to put the oem springs back on before taking it to the dealer so they can’t claim the springs are causing issues.

[B1RMA]

29 minutes ago, Jgtcracer said:

Yea, though I’m not  convinced it was working even before I fitted them.  Certainly no difference before/after install.  I’m going to put the oem springs back on before taking it to the dealer so they can’t claim the springs are causing issues.

One would hope that Lexus service is a bit more grown up about such things. It raises the issue as to whether you will have to go back to them if you change over to the lower springs. So far my experience with Hedge End has been one of a helpful attitude when unbeknown to all the TPMS units fitted by the wheel place were not compatible with the Lexus system. Admittedly the guy who seems to service my car says he likes it and what I've done to it.

So hopefully you will encounter a similar helpful frame of mind from where you get yours serviced

[Jgtcracer]

21 hours ago, B1RMA said:

One would hope that Lexus service is a bit more grown up about such things. It raises the issue as to whether you will have to go back to them if you change over to the lower springs. So far my experience with Hedge End has been one of a helpful attitude when unbeknown to all the TPMS units fitted by the wheel place were not compatible with the Lexus system. Admittedly the guy who seems to service my car says he likes it and what I've done to it.

So hopefully you will encounter a similar helpful frame of mind from where you get yours serviced

As I’m still trying to work out the problem and if indeed one exists at all, wanted to put the car back to stock as it removes a complication that would exist whilst diagnosis is going on.  Should I find that we fix it for the problem to reappear once I put springs back on I’ll take it in with them  fitted, or get techstream myself.

As an reliability engineer, if someone came to me with a problem and modification has taken place, I’d probably put back to stock before getting too deep into an investigation.