arentz07

So, what's the deal with the different drive modes in the IS 500?

I've seen various impressions on this car, and video footage to suggest that the modes don't do exactly what I'd expect they do. For instance, if you watch TheTopher's track driving video, the car is in Sport S mode, but does not down-shift into the second turn on its own. What gives?


The Basics

The IS 500 features variable drive characteristics in three main areas:

1. Drivetrain: This refers to engine and transmission response. Settings are: Power, Normal, Eco, and Sport S+. Sport S+ is a hidden setting that is only usable in that mode and not available in Custom mode.
2. Chassis: This refers to suspension firmness and steering weight. Settings: Sport, Normal.
3. Climate: This refers to the energy-saving behavior or lack thereof in the climate control system. Settings: Normal, Eco.

In order to figure out what is going on here, it's helpful to look at the Custom drive mode options. In that mode, the user has access to the above options. So, a reasonable person may assume that the built-in drive modes in this car are comprised of some combinations of the above options. At surface-level, it may seem like the most likely combos are as follows:

Eco

• Drivetrain: Eco
• Chassis: Normal
• Climate: Eco

Normal

• Drivetrain: Normal
• Chassis: Normal
• Climate: Normal

Sport S

• Drivetrain: Power
• Chassis: Normal
• Climate: Normal

Sport S+

• Drivetrain: Sport S+
• Chassis: Sport
• Climate: Normal

Based on my over-8000-mile impressions, this seems to reflect how the car behaves. That said, it's also not entirely indicative of how the car behaves in the real world.

AI-Shift

With the third-gen IS, Lexus has introduced a feature they call AI-Shift, or G-AI-Shift depending on the application. This feature simply uses feedback from G-force sensors in combination with driver inputs to detect the style of driving that is being performed. For instance, in my 2016 IS 300 AWD, when the car was in Sport mode, the car would drive normally if I drove it gently. The only notable difference would be slightly increased response to the accelerator pedal. However, if I either floored the gas pedal, gave it significant braking force, or threw it hard into a corner, the car would recognize that I am driving more aggressively, and from that point onward, it would do things such as automatically downshift when braking and hold gears to near-redline. The owner's manual even mentions this function (without explaining how it actually works in detail). This feature was also present in my 2021 IS 350, but, Sport mode was programmed entirely differently. It was overall more aggressive all the time, so, driving the car in normal traffic in Sport mode was not a good idea. It also never seemed to really understand that 7/10ths driving is a thing. I had to absolutely push the car for it to wake up.

Thankfully, the IS 500 retains this feature, but the way in which is operates is vastly different between drive modes. Here's what I have observed so far:

• Eco: I didn't bother testing it, but I suspect G-AI-Shift won't work at all.
• Normal: It seems like it will do things like hold a gear if I accelerate aggressively, but it does not seem to auto-downshift as I approach a turn.
• Sport S: It takes a lot of convincing, but it will hold gears. It doesn't seem to auto-downshift easily, if at all. It likes to upshift at 7,000 RPM.
• Sport S+: It will downshift automatically very aggressively, even into first gear. It still upshifts prior to redline in most cases, even when pressing the accelerator down through the kick-down switch.

Of all the modes, it seems easiest to activate AI-Shift in Sport S+, though this could simply be because the accelerator input is ramped-up in that mode compared to other modes. On a twisty road, Sport S+ seems to work extremely well. It takes a few seconds for it to activate - in my experience, I have to hit two to three corners aggressively before it will "wake up".

Shifting Gears

There's another element of how the IS 500 drives that you may have been thinking about - transmission shifting behavior. That's not to describe the shift schedule (i.e., at which RPMs it should change gears up or down), but rather, the manner in which shifts are performed. Sometimes, the shifts are smooth and slow, but others, they are firm and fast. Let's look at an obvious example:


In this video, a viewer can easily observe the difference in shifting between Eco and Normal modes and the Sport modes. It seems that the faster shifts are more likely to occur in Sport S and Sport S+, respectively, based on throttle input and the temperature of the transmission fluid (maybe).

When in Manual shifting mode, the quicker shifts are much easier to command - all that is needed is a decent amount of throttle input (maybe 50% or more). This seems to hold true regardless of drive mode, though I've never tried Eco with manual mode before. If you are not sure whether the car is fully warmed-up, switching to manual mode and downshifting a few times should make it apparent. If a downshift occurs such that the new engine RPM is above 2000, the RPM should automatically rise to meet the needed speed for that gear - i.e., the downshift will be blipped. If this doesn't happen, either the engine RPM are too low or the fluids are not yet up to operating temp.

In summary, here is how the shifts behave:

Normal shifting mode:

• Eco
• Normal

Sport shifting mode:

• Sport S (or Power setting in Custom mode)
• Sport S+
• When Manual (M) is selected on the gear selector

A final note on Sport S+

From what I can tell, Sport S+ seems to also cause the car to select a lower gear upon entering the mode, if a sufficiently low gear has not already been selected. Of note, this does not occur when selecting Sport S. It also seems to have the car stay in lower gears longer/more often compared to Sport S, regardless of driving style. That said, I have managed to drive around "normally" in Sport S+ auto before without too much trouble. This transmission behavior is probably tied to the Sport S+ drivetrain setting.

Anyway, I plan to flesh this out some more, but for now, wanted to ask if these observations align with what everyone else is experiencing.

Vinnigan

Sport S+ definitely changes the steering weight though. It looks like the steering is connected to the Chassis setting then?

arentz07

Yes most likely. (This was mentioned already in the break-down of the various driving settings.)

Oreois500

Only drive mode I haven’t tried is sport +, but saw some posts that post a chart from the lc that shows various drive modes with settings for powertrain and chassis. Was going to test custom mode with powertrain and chassis on aggressive settings and see how that compares to sport s. From the other posts, sport s seems to only have powertrain in power mode but chassis in normal. Currently my custom mode has been powertrain normal, chassis sport and the steering feels very heavy compared to sport s. Maybe having custom with aggressive settings would save me a few twists to sport + 🤷🏻‍♂️

arentz07

Yes, and I believe that is how I indicated it above. The gotcha is that Sport S+ also has a higher baseline setting for the transmission behavior compared to Sport S. For example if I am in Normal mode and switch over to Sport S, nothing happens immediately. But if I then go to Sport S+, it will instantly drop a couple of gears.

If you haven't tried Sport S+, I strongly recommend it.

Oreois500

will do! We’ll see how it goes. Do you think custom aggressive settings would be like sport s powertrain and sport + chassis?

GoHorns

The setting for Sport + can only be accessed in Sport +. You don't get to use them for your Custom settings.

Eco

• Drivetrain: Eco
• Chassis: Normal
• Climate: Eco

Normal

• Drivetrain: Normal
• Chassis: Normal
• Climate: Normal

Sport S

• Drivetrain: Power
• Chassis: Sport
• Climate: Normal

Sport S+

• Drivetrain: Sport +
• Chassis: Sport +
• Climate: Normal

arentz07

Well that would explain it if true. Is there actually a chassis difference between Sport S and S+? I haven't been able to tell.

In any case, I updated the original post, since I can tell there's a clear separation between S and S+ when it comes to the drivetrain.

howard500

iTrader: (1)

If I want to drive sporty, I skip S and just go to S+ in manual mode. The auto is too unpredictable and feels slower. All other times I would be in Eco or Normal. I actually like Eco for cruising since it smooths out the throttle and keeps the RPMs low.

Oreois500

custom mode with chassis on sport felt stiffer than sport s

GoHorns

It is stiffer in Sport Plus than Sport.

I can't find it, but I specifically remember reading that Sport Plus settings can only be accessed in it. My ideal setup for the highway would by a sport plus drivetrain and normal chassis.

spotxc

iTrader: (5)

I've currently been using custom mode when driving which works the best for me:

drivetrain - normal, when I tried sport it is actually a jerkier ride when it upshifts upwards of 3k rpms
chasis - sport, the whole time I drove this car, I wanted just the chasis in that sport s+ mode
climate - normal, Does it really matter? lol

I think sport chasis is how this car should drive normally anyway. Its perfect, you really don't lose any comfort, but it reduces the body roll and gives it better turning

As for this car's drivetrain, I can't figure it out. If I had to describe what I wanted, it would be normal with increased throttle responsiveness. The sport mode seems useless to me. It takes normal and makes it more jerky without a big difference in throttle response or holding high rpms. Sport S + seems a little too aggressive for normal driving as I don't need such aggressive downshifts and rpm holding. However for all out, its good.

Normal with sport chasis and an increase in throttle response with less pedal push travel would be ideal ( also a little bit more proportionality). It feels like its either 25% or 85% throttle with normal. The pedal cant increase proportionally to your push. Its lazy or its like I'm an animal lol.

arentz07

I have this same setup for Custom, mainly because there's not a default way of having this combination of options. I like the more progressive throttle pedal in Normal. If I want to drive it fast, I can just go to manual mode.

Edit: I drove a little in my Custom mode today, and can confirm the steering is much heavier than it is in any other mode except for Sport S+. This seems to confirm my suspicion that Chassis: Sport is what's used in Sport S+.

gcmak

I say yes. Steering is heavier in Sport already, with no additional heft added in S+. Find some empty lot and coast while moving the steering wheel left and right and change the modes. The weight change is easy to notice.

I know you didn't try eco. I do use eco more often than not for the mundane stuff like traffic and even city driving. You do notice the HVAC tone itself down - ac compressor runs less often and fan speeds run lower (in auto). The dulled throttle response is what gives it the 'eco' ness, and I don't mind this in quite a few situations I find myself in. Trans wise, I don't think its any different than driving with a lighter foot in Normal. Where the dull throttle mapping in eco makes it seem like the trans is in another mode is if you command full power suddenly, it really takes an extra second for things to come alive.

arentz07

I disagree on the steering between S and S+. I would say the steering between Normal and S is barely different - ever so slight. But in S+, on-center heft is obviously higher, and it feels a little more reluctant to steering corrections while in a corner. Honestly, I like the heavier S+ steering a lot.