lsft

If you can repeat it, please do take a video of it. I've definitely seen the behavior in Auto.EV/HV mode.

ct6978

I'll give it a shot, the full battery downhills should be doable as we live uphill and it typically comes on at the first stop sign after a full charge. The others occasions (steep downhill breaking, flooring uphill climbing) aren't consistent, and I'm on winding mountain roads, so really need both hands....but I'm trying to figure out what exactly is the trigger in these cases. I turned on the tach display in EV mode specifically to figure this out after I first noticed it.

The ICE really helps with engine braking on the steep grades, of course you're losing recharging.

Kusala

This is quite peculiar.

I also live in a mountainous area and require many KM’s of uphill driving to get home. As long as I have EV capacity I have not once had the ICE come on. The speed limit ranges anywhere from 50KM/H to 90KM/H.

ct6978

Try this, works almost every time, for me and my wife:

• Charge the batter completely - 100% and charging shuts off
• Ensure you have the tach showing in EV mode (I think I changed the normal driving mode display to 'sport')
• Start the car and drive downhill, braking along the way, the trick here is not to exhaust any battery, just continue regen braking

The ICE seems to come on for us about after about 400m elevation drop and about 2 km distance. We have a stop sign there and that's about when I notice. Once I saw it happen I asked my wife and she's also confirmed it happens for her. We are in normal drive mode (not sport or sport s) or custom (normal drivetrain, sport shocks).

The ICE comes on idling per the tach at warmup RPM. If I didn't have the tach on I probably wouldn't notice. It shuts off again after a short period similar to starting in HV and warming up. The ICE also seems to persist on for while after switching to EV mode depending (seemingly) on whether it was warmed up and how my right foot is behaving.

In my downhill case, or switching to EV mode, although the ICE is running, it feels 'disengaged', so I believe the EV motor is providing propulsion.

What's annoying to me is I'm trying to avoid the ICE coming on at all for short trip days as then we're seeing short on cycles w/o the opportunity to get up to temp. When this happens, I almost feel obligated to run the ICE again to get it good and hot.

Just out of curiosity, how does the car handle a completely fully battery and regen braking? Does the motor disengage it's electrical generation function?

ct6978

fyi, for the incredulous, perhaps your right foot has been affected by the feel of luxury, evidently this happens in the RAV4 Prime as well:

https://www.rav4world.com/threads/ic...v-mode.318033/

My favorite is the catch all "When the system determines that the gasoline engine needs to be started."

The aggressive uphill in sport mode instances have definitely been "When power is needed temporarily, for example when the accelerator pedal is depressed firmly or when accelerating suddenly." as I'm used to more power than this car has.

Here's another thread:

https://www.reddit.com/r/rav4prime/c...ne_in_ev_mode/

I think my downhill full battery experiences match the post "been happening to me lately when fully charged and I use too much regen braking early on."

Kusala

Anywho, perhaps what is happening is the equivalent of a kick down into a lower gear when the accelerator is pressed fully. Next time I'm driving I'll give it the beans and see if the ICE kicks in. Coming from an AMG I've enjoyed less spirited driving in the 450 😁

NSXT

This is from Prius Chat:
"There are different conditions that will cause the ICE to start. If your battery is fully charged and then going downhill, that's probably causing it. Secondly, the software isn't going to be looking at your speed per se, however yes speed can play a role in whether the ICE starts. In the regular prius the ICE starts when the battery pack is near it's maximum charge. The software controls the rate of charge into the battery pack. Once the battery nears its maximum charge the charge rate will drop and to maintain engine braking the ICE will start and the braking will be part ICE and part MG. This is all normal behavior and is to maintain battery life over the long haul."

Prius Chat

RAV4 Prime and NX450H+ are derived/enhanced from Prius Prime and the process/logic will be similar.

Also during winter time, when the temperature drops to -9 Celsius during EV mode while the heat is on, the ICE will kick in as the Heat pump is not efficient enough to provide heat generation.

In EV mode during winter, if you turn on the front windshield defrost, the ICE will kick in as well.

I am coming from Prius Prime while waiting a delivery next year for a 450H+ to replace my wife's NX300h

darkloki

Okay so how do I get the whole 84 MPGe? because as I understand it I'm either getting RV Range or the 36 MPG. Perhaps I don't really understand what MPGe even means or what that average is saying or is about.

The second thing I guess I want to know is what's the most efficient way to drive this car? I live in Irvine a county within Orange County. And right now I'm just driving in EV mode when I'm driving in Irvine but if I go to LA or another neighboring city/town I drive in Hybrid Mode. Is that the best way to drive this thing?

Thanks.

NSXT

The goal is to use EV as much as we can. The more EV we use, the more saving we get and the MPGe is the combination of the two. That is how you get the mpg being displayed in your console.

Check this out for some of the best combo driven: Optimal Driving Mode Select and EV/HV drive mode combo?

If it is too much of a hassles, just enjoy driving without doing anything as the car itself auto-combination will do better than a regular NX Hybrid once the traction battery reaches to zero (internally should still have 20% reserved).