Ex-gen 4 owner about to get a 2021 Prime

Discussion in 'Prime Main Forum (2017-Current)' started by pakitt, Jan 25, 2021.

  1. pakitt

    pakitt Senior Member

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    I haven't been on the forums for quite a bit. It's good to be back.

    I had to sell my beloved Gen4 Prius back in Feb. 2019 as I moved out of Germany to Alice Springs (Australia). Because of the limited use of a car here (there is nowhere to go), I bought a small 2017 Yaris. She does her job well, but a world apart from the Prius. Starting with the (pretty horrid, I must say) fuel consumption. At least gas is relatively cheap here.

    I am moving soon to the USA and planning to get a 2021 Prius Prime Limited in red (stock permitting.) Enough with gray cars. :D I looked at other options from competing manufacturers, but the Prius is still the only car that looks, and is, modern, with innovative and different styling, while returning impressive fuel consumption. I have trouble driving cars with traditional dashboard setups and gauges behind the steering wheel, just to name one thing.

    Being a two time Prius driver (Gen3 and Gen4), I have a few questions for the Gen2 2021 Prime drivers and all other great Priuschat members out here:

    1. Excluding the plug-in features, does the Prime work, if at all, any differently than a Gen4? Are the specs of the ICE, electric motor, and generator any different between the two?
    2. Is the mpg markedly better in winter, considering the introduction of the heat pump?
    3. Any other notable differences in mechanics and driving vs. a Gen4? (I read of a "Predictive Efficient Drive" feature...?)
    4. How much and in which way is the TSS2.0 better than a 2016 Gen4 vanilla Prius (which I guess had the TSS1.0)? On the 2016 Gen4 I had significant issues with the automatic headlights (way too aggressive.) The DRCC, in very hot weather behind preceding trucks, and highways with sharp bends, would suddenly brake the car, detecting a ghost vehicle in front of me.
    5. Is the Road Sign Assist (RSA) any better, or still just a gimmick?
    6. Are the LED Headlights in the Limited trim adaptive? or is it only an EU feature?
    7. Suppose I deplete the battery's EV-only portion (that is, the part that gets used before the HV mode kicks in), and I am going downhill. Will the ICE charge the extra battery capacity now available vs. a Gen4, or will it merely max out the "hybrid" portion of the battery and start using the ICE as an engine brake? (like when setting the car to B or going down a long slope and wasting any possible energy in heat pumping air in the cylinders, instead of storing it in the available bigger battery of the Prime)
    8. Is the "charge mode" a marketing gimmick, like EV-mode almost is/was on the Gen4 and Gen3 (helpful in a very few corner situations), or does it have an actual practical use? I cannot see myself using this feature, polluting the air while charging the battery inefficiently in a standstill. And I don't know how much of a benefit there is using it while in a daily commute of a few miles, or during a long highway drive, if it has a significant mpg hit. If not using the "charge mode", does the Prime simply continue charging the whole battery until it is full (wouldn't that be fantastic), or instead it merely trickle-charges the "hybrid" portion, once it is full (like the Gen4 does)?
    9. Is the red paint the same "special" red introduced with the Gen4 back in 2016 (that is, with an extra coating that would reflect more sunlight and lead to less cabin heat, if I remember correctly)? Or is it now merely "another color"?
    10. Is the hybrid "portion" of the battery a physically separate part of the battery pack, or is it simply a "logical" bucket set to simulate the same size of the Gen4 battery pack? (then the battery logic will store the electricity where it wants)
    Thanks for all the information you can share - and it is good to be back on Priuschat!
     
  2. schja01

    schja01 One of very few in Chicagoland

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    You will want to use Charge Mode when you test drive the Prime and the dealer didn’t charge the car before you arrived.
    Red costs extra and has the Clear Coat.
    Only one physical traction battery. I believe the electric motors are larger.
     
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  3. JirkaV

    JirkaV JirkaV

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    Engines are the same, just slightly different gear ratios (engines spin a tad faster than on regular Prius for a given speed). One major technical difference is that plug-in has a special one-way clutch that allows it to use both engines to drive the car under specific conditions (something the regular Prius can't do, only MG2 can drive the car there).

    Battery behaves just as you'd expect. If you go downhill, your battery will charge to full before ICE kicks in to drain energy. I have managed to fully charge the battery from "EV zero" to full twice, but it's unlikely to happen in Australia (not enough altitude difference).

    Never used charge mode as it does not make sense (except for the rare situation mentioned by schja01).

    The "HEV" portion of the battery is only a logical concept (also displayed on the dashboard). The battery is physically one unit with all cells being equal.

    Can't comment on RSA as I had it switched off since day 1 (doesn't work well in Europe) and also have LED Matrix lights on the EU model (which works pretty well) so can't comment on lights. Predictive Efficient Drive is available only on some markets, not in Europe.
     
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  4. schja01

    schja01 One of very few in Chicagoland

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    With the lockdown being as it is I have been using charge mode instead of wall charging just to burn off fuel before it gets old. Another special case use.
     
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  5. Salamander_King

    Salamander_King Senior Member

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    Welcome back.
    I have never driven Gen4, so I don't know the direct comparison between those two cars. But for #7 and #8 questions, I think my comment on this thread answered. 2021 Prime | Page 4 | PriusChat
     
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  6. dbstoo

    dbstoo Active Member

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    I've used the charge mode in a couple circumstances.
    a) Showing off: Right after buying the car I drove it 500 miles to visit my mom. As I crested the last mountain and began the last 15 miles into her valley I had about 6 miles of range left. I used the charge feature to fill the battery to 80% so that I could show mom the EV feature.

    b) Eating gas: After a year of not using the gas engine (thanks pandemic) I began to worry about stale gas in the tank. Note that there were no issues with the car, I was just being proactive. I stopped plugging the car in for a few weeks and took daily trips through the local valley. It looked like I was getting about 1 mile of EV range for every mile that I drove and showing around 25 MPG. I could be wrong on the MPG. I used up half of a tank and then went back to normal daily charging.

    Dan
     
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  7. srivenkat

    srivenkat Active Member

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    I recently bought a 2017 Prius Two and had a 2020 Prime XLE (TSS 1.0) for 4 months before replacing with a 2021 Prime XLE. Here are my thoughts.

    Excluding the plug-in features, does the Prime work, if at all, any differently than a Gen4? Are the specs of the ICE, electric motor, and generator any different between the two?
    @JirkaV already answered; only one ICE engine but two motors that drive, IIUC.

    Is the mpg markedly better in winter, considering the introduction of the heat pump?

    IIRC, heat pump is only used while in EV mode > 14F. Otherwise, ICE turns on to provide heat. So, it depends on where you would live in the US.

    Any other notable differences in mechanics and driving vs. a Gen4? (I read of a "Predictive Efficient Drive" feature...?)

    The Prime feels heavier and more composed than the 2017 Prius Two. Conversely the 2017 Prius steering feels lighter.

    How much and in which way is the TSS2.0 better than a 2016 Gen4 vanilla Prius (which I guess had the TSS1.0)? On the 2016 Gen4 I had significant issues with the automatic headlights (way too aggressive.) The DRCC, in very hot weather behind preceding trucks, and highways with sharp bends, would suddenly brake the car, detecting a ghost vehicle in front of me.

    The 2021 Prime (TSS 2.0) steering feels heavier and more measured than the 2020. I had more trouble maintaining straight ahead driving on the interstate on the 2020 (TSS 1.0), especially when I had the LDW on, which I suspected made the steering lighter and hence more susceptible to overcorrection by a human. With DRCC, I am annoyed by the sudden acceleration when the path in front becomes clear. I think at least in ECO mode, it should have been made to accelerate gradually/economically like how a human would. I think OpenPilot (fully compatible with TSS 2.0) is smoother.

    Is the Road Sign Assist (RSA) any better, or still just a gimmick?

    I have found it useful where I drive; seems to catch the signs, which I usually tend to not pay attention to; something better than nothing.

    Is the "charge mode" a marketing gimmick, like EV-mode almost is/was on the Gen4 and Gen3 (helpful in a very few corner situations), or does it have an actual practical use? I cannot see myself using this feature, polluting the air while charging the battery inefficiently in a standstill. And I don't know how much of a benefit there is using it while in a daily commute of a few miles, or during a long highway drive, if it has a significant mpg hit.

    I see a couple of typical use cases for Charge Mode:
    1. You are driving on the highway and want to replenish the EV charge because you will have an opportunity coming up to use EV mode in city traffic and such after exiting the highway. I don't think there's a significant MPG hit (see threads on here that discuss in detail) relative to the charge that it will produce and the savings of avoiding HV mode later.
    2. I look at the Prime as two car systems in one (conjoined twins, if you will), whereby you need to care for both the traction battery (use departure charge scheduling) and the ICE. Toyota recommends burning ~6 gallons in a year which comes to ~1 mile a day. So, Charge Mode would be a great way to exercise the engine once a week so it gets hot enough with burning ~7 miles worth of gas, if you are only routinely doing EV driving. This also assures ICE availability when you do actually need it.

    If not using the "charge mode", does the Prime simply continue charging the whole battery until it is full (wouldn't that be fantastic), or instead it merely trickle-charges the "hybrid" portion, once it is full (like the Gen4 does)?

    Unfortunately, no, HV mode engine run doesn't markedly charge the EV portion beyond what it takes from it. But excessive regenerative breaking (which a long downhill would result in) would charge beyond what was taken, I think.
     
    #7 srivenkat, Jan 25, 2021
    Last edited: Jan 25, 2021
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  8. dbstoo

    dbstoo Active Member

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    However, a long incline in HV mode will continue to add the extra generated power to the battery. Driving down a 5 mile long 6 percent grade added significant range to the battery.

    Dan
     
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  9. jerrymildred

    jerrymildred Senior Member

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    We don't have the 2021 of either car, but we do have a 2017 Prius and a 2017 Prime. So I can't answer all your questions, but I'll tell you what I can. And hopefully refine and add to what's already been given.

    ICE is the same and MGs are the same, but as already mentioned, the sprague clutch in the Prime lets MG1 help power the car in EV mode. Also the Prime has different gearing for MG2. Professor Kelly explains at about the 11:00 mark in this video.


    The predictive efficient drive is handy but not life changing. It's just a bar on the HSI that shows you what the car says is the most efficient accelerator pedal position for the current situation. But it doesn't always seem to know if you're going uphill or down, if you're only going a few feet, or if there's a truck breathing down your neck.

    I don't have it afaik. I wouldn't want it. It's my job to read the signs and watch the traffic, not be stating at the dashboard full time waiting for it to read signs for me.

    As mentioned, adaptive lights are not available in the lowly US of A. We are not worthy. BUT, the headlights on the Prime are way way way better than the regular Gen 4 lights. Not perfect, but seriously illuminating.

    As mentioned, if the hill is big enough, your braking induced (or coasting) regeneration will keep on going to the battery till it's full. But it takes a big hill. The border on the battery between EV availability and HV only is stretchy. If you've used all the EV range and you're going down a mountain pass, it'll keep showing no EV as it builds charge and then suddenly show almost a mile.

    Also, if the car is in HV mode and you put it in B mode, it's going to act like a regular Prius using the ICE as an air pump. What's cool, though, is that if you're in EV, putting it in B increases the regen rate rather than spinning the ICE. Very useful on long, steep grades in the mountains. Not worth the effort on a normal hill.

    Mostly useless as pointed out by others, What many Prime drivers don't seem to have noticed is that the car uses charge mode all by itself when the conditions are good for that. So, if you're on a flat road doing 50 mph in HV mode, the car needs so little power to maintain speed that the ICE will run at a higher, more efficient, rpm and throttle setting than needed and dump the extra power into the battery. After a while, the ICE will shut off and it'll go into EV all by itself for a mile or two. And then it repeats, getting you 65-70 mpg or better. The regular Prius does that, too, but not as well.

    In HV, it'll want to keep the battery close to the SoC it had when it went into HV mode.

    Subtle differences. Perhaps @Tideland Prius can explain.

    Already answered well. Think of the "portion divition" as a float switch in a barrel. When the level is too low to turn on the switch, EV mode is disabled. When it's high enough to close the switch, EV is available.

    But don't forget that, even in HV - even with no EV range left - the Prime will frequently shut off the ICE on its own when certain conditions are met and will do so more readily than the regular Prius.
     
    #9 jerrymildred, Jan 25, 2021
    Last edited: Jan 25, 2021
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  10. pakitt

    pakitt Senior Member

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    @srivenkat - thanks ever so much for the answers. A few comments on my side.
    DRCC I had the same problem as you had with my Gen4 - I also had the issue that in Germany they drive very aggressively on the highway: fast accelerations and last minute braking tailgating. The DRCC was mimicking that, so I ended up using the normal cruise control, and DRCC only in stop&go traffic out of town or in a long traffic jam. And even there, sometimes better to use your own feet.
    ECO mode smoothes out a bit the reaction, but I agree with you, it should accelerate more smoothly and more mpg-aware rather than stomping on it. It was irritating. It's like as if the person who programmed it, drives a Ferrari, and put the logic in a Prius.

    Regarding Charge mode I will test it myself and see if I can reproduce a driving scenario, at the same temperature, same route, to see the mpg hit using and not using Charge mode. Otherwise, plug it is all the time and for the rest of the time, either EV-Auto mode or actively choosing which mode depending on the route I need to take (short trip to the nearby store or full blown highway trip).

    As for the HV mode charging the battery beyond the "hybrid" level, I see there is no consensus yet of what happens. I guess I will test it when in Colorado. I expect many long down slopes there... :)
     
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  11. pakitt

    pakitt Senior Member

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    @jerrymildred thanks for all the answers and information!
    From what I read, the Prime in HV mode is actually better than the Gen4. It sounds almost like a Gen4.5. Yeah! When commuting in Germany (mostly, but not just, city traffic), I would consistently get 50/60% EV mode vs ICE running. It seems the Prime in HV mode can get even more! Yeah!

    To comment on your answers:
    • The Predictive Efficient Drive then seems to be more of a gimmick than actually a "life-changing" feature. It is like the score bars introduced on the Gen4: I got better scores looking at the road and predicting traffic behaviors (including far better mpg) than trying to use the information from the MID.
    • Gen4 LED headlights (standard in the EU) were a night/day improvement vs the halogens in Gen3. If the LED lights on the Prime are that much better than LED headlights on Gen4, wow - looking forward to it (even if they will sadly not be adaptive).
    • The Gen4 would take "forever," even when the battery was completely full going down a very long/steep slope (there are a couple between Germany and Austria), to switch from regenerative braking to using the ICE as an air pump. It seemed like the last bar would take forever to be full. (Actually I wonder if the Gen4 battery indicator is linear or not.) Then I could enjoy speeds of up to 100km/h-60mph using the battery for about 1km/0.6mi after that, before it would revert to regular HV behavior.
    • Interesting to know that B mode is a bit more helpful in charing the battery instead of immediately converting the ICE to air pump when releasing the accelerator. I will still drive in D all the time and use the brakes instead even when going down hill. If you don't brake hard, the Prius should already use as much regeneration as possible. And then convert to "ICE air pump mode" once the battery is full. I never really used B mode on my Gen4. With the Prime having such a big battery, I expect the regenerative effect to be available most of the time (if you don't brake hard).
    • If going on a flat road at 50mph, with the ICE in "happy mode" (as I called it the first time I saw it on the Gen3: it happens when the ICE drives directly the wheels with no involvement of the battery/electric motor and you get the most efficient usage of fuel), the Prime decides it has enough energy to go in EV for "long" stretches, that is fantastic: "0 mpg" (well it is not really 0mpg because the electricity has come from somewhere) has quite the effect on the overall average, even on longer drives!
    • "In HV, it'll want to keep the battery close to the SoC it had when it went into HV mode.": so this means that if the EV-only portion of the battery is at, e.g., 63% when entering HV mode, the HV system will never really attempt to use any of that charge to drive around - is this correct?
    • I think there is a fine line between how much you gain in mpg vs how much it "costs" to use up and regenerate extra current while in HV mode. I think in the Gen4 (and Gen3 before that) the battery is as big as it can be to allow the highest efficiency vs overall car weight & cost of "filling it up" with burning gas while driving around.
     
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  12. pakitt

    pakitt Senior Member

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    @srivenkat what is OpenPilot?
     
  13. SciRunner

    SciRunner Junior Member

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    If you have an Android phone or like Android Auto, you need to get the LE lower model. AA is not available on XLE or Limited. Unless for some rare miraculous chance Toyota sends an update or a customer improvement campaign similar to the Apple Carplay “upgrade” for 2018 Camry and other models.

    A pro for XLE and Limited models is standard charging port lock. Not even an option on LE (I think). Keeps ICEing pranks in check.

    No spare tire on all PriusPrime models. You get a tire repair kit or purchase a donut or full spare and keep it in the car.

    Storage is less though I’ve never looked at the Prius Gen 4. I had a 5.7L V8 Tundra DC with a 6ft bed so storage is relative.
     
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  14. Salamander_King

    Salamander_King Senior Member

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  15. jerrymildred

    jerrymildred Senior Member

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    It sounds like you're gaining a pretty good understanding of the Prime already!
    I think it is. It's not hugely better, but it's very noticeable. My wife's Gen 4 is still a very impressive car to drive. My Prime just has a little more "impressive sauce."

    This is often true for me. A high eco score doesn't always get you more mpg. But it often does. The predictive efficient driving bar is a good teaching tool for people new to the Prius, though.

    I would be surprised if it was linear. People here on PC have documented that in earlier generations the #5, 6, & 7 (iirc) bars represent more energy than the others. And the Prime will go up to 84 mph in EV mode. Not sure why you'd want to, though; it would burn through the battery charge in a big hurry.

    Indeed! It's mind blowing in the mountains. We left the top of Grand Mesa in Colorado with about 10% EV showing. Had a full charge showing at the bottom. Continued on EV the rest of the way to I-70 and the drove up I-70 (eastbound, uphill) for a long time. I''m guessing we stayed in EV for maybe 50 miles. There were places on the long drop that B mode made it too slow, so I had to either put it back in D and brake a little or else nudge the gas pedal a little. D was much simpler for me.

    When the Prime comes out of its self imposed EV and back to ICE power, it runs the ICE at a power setting that gets the most distance from a unit of fuel that it can and putting the energy not needed for propulsion into the battery. So, while not 100% efficient, it is more efficient that running the ICE at a lower and less fuel efficient throttle setting.

    Yes and no. It'll borrow some of it in HV mode, just like a regular Prius. So, if you have 63% indicated when you put it in HV, you may have a percent or two more or less when you get to your destination and shut off the car. It depends on if it's just finished storing up juice for the next EV portion or just finished the EV and is about to pay back the loan.
     
    #15 jerrymildred, Jan 26, 2021
    Last edited: Jan 26, 2021
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  16. Tideland Prius

    Tideland Prius Moderator of the North
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    @pakitt is thinking of the Lime-Green Thermal Tec as the heat-reflecting paint, which isn’t available in North America.


    The red is a special 3-coat paint with a base red layer then a special reflective layer then the top coat. The current one is Supersonic Red (or Emotional Red 2.0). It’s slightly brighter than the red introduced in 2016. The change is subtle and you might not even notice the difference unless a 2016-2019 is parked next to a 2020+.
     
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  17. pakitt

    pakitt Senior Member

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    @Tideland Prius - then it was the green color I remembered. I don't think it ever sold outside of Japan because it was honestly quite horrid :D
    Red is therefore just "shinier". The extra "feature" is then the additional reflective layer before the top coat. Thanks for the explanation!
     
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  18. ETP

    ETP 2021 Prime(Limit),Highlander HYB Plat,B52-D,G,F,H

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    I have had all the models except version one and to me the Prime is a higher quality car. So far!!!!
    Side question is the wind chill pearl a different shade than the Pearl in previous Prius?

    Also what ever happened to the detailed paint description that Toyota always bragged about.
     
    #18 ETP, Jan 28, 2021
    Last edited: Jan 28, 2021
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  19. pakitt

    pakitt Senior Member

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    (Hopefully) one last question: how do you differentiate a 2020 Prius Prime vs a 2021 model?
    Are there any evident physical differences, things I need to look for when I get the car at the dealer, to make sure they are not giving me the older model?
     
  20. Salamander_King

    Salamander_King Senior Member

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    I have not seen the 2021 model yet, but I think they are mostly a carryover model only differing by TSS2.0 implementation and a few other safety features and infotainment. I might be wrong, but the external look maybe identical. In any case, if the Monroney label and VIN indicate it is 2021, it must be real. Otherwise, it would be a big fraud.
     
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