Hybrid RAV4 AWD Hill Descent Control

[Mrs Scoobington]

Hey all,

Hoping for some feedback.  Thinking of the above variant, but one essential for me is Hill Descent Control.  I am amazed the RAV doesn't have it when the Yaris Cross AWD does!!

Anywho, guy at the dealership said switch into low gear and you'll slow the engine to get the same effect, BUT a) CVT gearbox....how? and b) engine braking isn't the same as the 'crab crawl' of the HDC....or so I believe.

Any thoughts re the above would be appreciated.

Cheers

 

[Nick72]

I was also surprised at this. Had come from a Peugeot 3008 hybrid4 GT300 PHEV and that had it. Stops you having to worry about brake pedal and the accelerator, and just concentrate on steering as you crawl downhill at a constant speed. 

On the gear stick there should be S mode. And a plus and minus selector. You can nudge the gearing down or up which probably maintains the CVT in a particularly gear ratio region. I've not tried this yet. It's probably also the only reason I can see for using the flappy paddles on my GRS.

[philip42h]

1 hour ago, Mrs Scoobington said:

Hoping for some feedback.  Thinking of the above variant, but one essential for me is Hill Descent Control.  I am amazed the RAV doesn't have it when the Yaris Cross AWD does!!

I had a "hill descent control" function on my RAV 4.4 (D-CAT Auto) and used it twice - never in 'anger'. It allows the driver to set a descent speed and holds the car at that speed without further intervention from the driver.

The 4.5 hybrid doesn't have anything of that sort, and, honestly, I don't miss it - light pressure on the brake pedal will initiate regeneration, slow the car and prevent it for running away.

I was a little surprised that the Yaris Cross (AWD) had such a function, but it does! It's not Hill Descent Control but a Downhill Assist Control (DAC) system. From the description in the Owner's Manual, when switched on, it simply applies the brakes for you.

I'm surprised that you would regard it as an essential ... 😉

[Cyker]

It is a valuable assist when going down steep slippery hills!

The good ones avoid locking the wheels, which is easy to do when braking manually in such situations in a normal car!

One nice thing about hybrid regen braking is it's naturally 'anti-lock', as if the wheels lock up it can't regen so the wheels turn again etc.

 

[NASY]

I regularly, like every day, use S1 setting to slow descent down my driveway and it is very effective at delivering a significant amount of regenerative braking. In particularly slippery conditions I would have hitched the handbrake in the past however no hitching is available on modern handbrakes as they are either on or off.

[ROCKETRON]

Isn’t this what trail mode is for, to give more control when going slowly over rough terrain, altering throttle response,amount of power applied to rear electric motor and putting power and braking on individual wheels ? 

[philip42h]

1 hour ago, ROCKETRON said:

Isn’t this what trail mode is for, to give more control when going slowly over rough terrain, altering throttle response,amount of power applied to rear electric motor and putting power and braking on individual wheels ? 

No, the AWD does all of that automatically to deliver the best possible traction. That doesn't help when going downhill though.

Trail mode reduces the level of braking / power reduction to allow increased wheel spin in the desperate hope that the wheels will work their way through the loose stuff and find some grip! If you are in that much trouble, you probably shouldn't have gone there in the first place ... 😉

[Nick72]

46 minutes ago, philip42h said:

No, the AWD does all of that automatically to deliver the best possible traction. That doesn't help when going downhill though.

Trail mode reduces the level of braking / power reduction to allow increased wheel spin in the desperate hope that the wheels will work their way through the loose stuff and find some grip! If you are in that much trouble, you probably shouldn't have gone there in the first place ... 😉

Yep. Trail mode is escape mode. Allows you to do things like spin the wheels which is useful for rocking your way out or just getting out. 

[///MAZI]

I wonder if the short lived "Adventure" spec had this feature,  always liked the look of its front grill.

https://www.toyota.co.uk/discover-toyota/stories-news-events/toyota-rav4-adventure

[philip42h]

No ... at least I'm 99% certain that it didn't. The Adventure grade was simply an exercise in styling.

[Nick72]

6 minutes ago, philip42h said:

No ... at least I'm 99% certain that it didn't. The Adventure grade was simply an exercise in styling.

According to this at least, it does or did...

https://www.toyotaofrichardson.com/toyota-reviews/2024-rav4.htm#:~:text=Opting for the RAV4 XLE,and standard hill descent control.

 

[philip42h]

23 minutes ago, Nick72 said:

According to this at least, it does or did...

https://www.toyotaofrichardson.com/toyota-reviews/2024-rav4.htm#:~:text=Opting for the RAV4 XLE,and standard hill descent control.

You're importing misinformation from the US again, Nick. That article also states:

How Much Horsepower Does the 2024 RAV4 Have?

Under the hood of every 2024 RAV4 is a four-cylinder engine paired with an eight-speed automatic transmission, delivering 203 horsepower and 184 lb-ft of torque. The Adventure and TRD Off-Road models come with standard all-wheel drive

So, they are referring to a current model in the US rather than the Adventure grade from the UK a few years back. And the car in question is NOT a hybrid ... 😉

[Nick72]

4 hours ago, philip42h said:

You're importing misinformation from the US again, Nick. That article also states:

How Much Horsepower Does the 2024 RAV4 Have?

Under the hood of every 2024 RAV4 is a four-cylinder engine paired with an eight-speed automatic transmission, delivering 203 horsepower and 184 lb-ft of torque. The Adventure and TRD Off-Road models come with standard all-wheel drive

So, they are referring to a current model in the US rather than the Adventure grade from the UK a few years back. And the car in question is NOT a hybrid ... 😉

Fair point Philip but the more general point and reason for posting is Toyota has included descent control on at least one other RAV variant. We can assume from that they saw a need or that folks had a need.

It may be the case that the need or ease of implementation was tied with the automatic gearbox used in the example from the USA. And that Toyota figured there wasn't a need on the hybrids or PHEVs because of the substantial slowing down effect of regenerative braking and or with further application of the S +- gear selector? Or, because it was too hard and costly on our models. Or a bit of both?

Interesting there's lots of discussions on Reddit about this. Views expressed range from setting the cruise control to a very low speed (I don't know if this is feasible or advisable) or use S and a low gear (high regen, with engine mechanically in the loop). 

 

[philip42h]

51 minutes ago, Nick72 said:

Fair point Philip but the more general point and reason for posting is Toyota has included descent control on at least one other RAV variant. We can assume from that they saw a need or that folks had a need.

And, indeed I had descendent control in my 4.4 D-CAT Auto. The key point here is Auto - it is implemented within the automatic gearbox (mainly) and 'disappeared' along with that auto box when the RAV4 went hybrid only in the UK.

The US is a different world ... 😉

[Hadrian1]

I've never had the need for it.

[LPJR]

I am new to the RAV4 PHEV world having never driven an automatic for around 15 years. Things have changed a little bit. 

I was intrigued with the S1 option for downhill. So I did a possibly pointless test on the road I have to take as I leave my house. It is approximately 75 meters long with a 16° degree decent. In D, normal mode I crawled on to the decent and rolled down the hill reaching 30mph just over half way where I applied the brakes. Repeated next day in S1, the vehicle reached 14mph and maintained that speed until I applied the brakes near the bottom. 

It would have been nice if that speed was below 10mph. I will be avoiding that road in snowy/icey conditions.