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Engine Maintenance Mode

Discussion in 'Prime Technical Discussion' started by Tideland Prius, Apr 16, 2019.

  1. bruceha_2000

    bruceha_2000 Senior Member

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    I'm seeing GOM of high 31s. Still not warm here but I've not had to go out in the coldest morning weather. That will change tomorrow when I leave at 5 AM :eek: to take my daughter to the airport. SUPPOSED to be low 40's overnight but I'm betting she won't go for "turn on your seat heater and zip up your coat".

    64°F for a high this coming Sunday. Hottest we've seen all year.
     
  2. Tideland Prius

    Tideland Prius Moderator of the North
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    Ensure “climate” is on in your charging schedule so that the cabin is pre-heated. That’ll reduce the impact.
     
  3. SteveMucc

    SteveMucc Active Member

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    even better... it should be able to learn based on location what the typical throttle setting is (averaged over multiple trips) at a specific location. It can then use that refine EV/ICE engine usage dramatically, using each to their best advantage. (ideally it would have elevation information included in the map to help along random routes).

    They're missing out on a lot of possibilities by not integrating the map/route planning with the EV/ICE control computer.

    I'd even go so far as to have a "non-guidance" mode route on the nav system just for the purposes of doing better energy management.

    I don't think these solutions would be particularly hard to do, it's really just a matter of sorting power requirements for the route and then applying the right source for the particular region (little bit more than that since a region change from ev to ice will require some energy to start the ice and that will need to be averaged in so you don't have a gazillion start/stops), but overall I wouldn't think it would be difficult at all to implement.
     
  4. jb in NE

    jb in NE Senior Member

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    GPS has elevation data embedded in the maps.
     
  5. Tideland Prius

    Tideland Prius Moderator of the North
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    Day 52 and counting with the engine remaining off. It last came on on Mar 31.
     
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  6. Raytheeagle

    Raytheeagle Senior Member

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    Very nice:).

    My commute forces the engine on each day:(.

    But at 2650 miles, I’m still on tank #2 of gas and still have range available(y).
     
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  7. Tideland Prius

    Tideland Prius Moderator of the North
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    Yeah I'm experimenting to see when this engine timeout (or I guess EV timeout) will occur. There have been a couple of instances where I had to spend time charging instead of going on the trip and returning in HV mode. The things I do for this forum ;)
     
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  8. Raytheeagle

    Raytheeagle Senior Member

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    All in the name of data:).

    I’ll be the catch can man(y).
     
  9. Tideland Prius

    Tideland Prius Moderator of the North
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    Day 77. No engine.

    It’ll come to an end soon since I’ll be doing a road trip but at least you’ll know it won’t come for at least 2.5 months if you do so.
     
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  10. Tideland Prius

    Tideland Prius Moderator of the North
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    Ended the experiment yesterday. Day 78. Decided to run the engine in HV mode to make sure nothing is awry. It fired up like normal and didn’t run loud or with high revs (did that so it’ll come on under normal acceleration and used the EV buffer to provide forward drive as the engine did its warm-up cycle. Drove it on the highway to allow for relatively light load and a scenario where I can keep the engine on.).
     
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  11. kevin.c

    kevin.c Member

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    Thanks for sharing the results with us!
     
  12. MSantos

    MSantos EcoAccelerometry

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    Humm... I would love to be wrong here but I have yet to encounter this engine maintenance mode yet.

    The car (Cdn Prime Advanced built and delivered in March 2018) is about to reach 14,000kms (8,700 miles). The gas in the tank is still the very same the dealer included on delivery. Yeah, yeah... I've used a bottle of stabilizer just to be sure. :(

    Anyhow, I've done approximately 700km in hybrid mode over a few long-distance trips last summer. Beyond that, the gas engine barely started over the winter months (make that "Winnipeg Winter" months) and the few times it did, its because I purposely forced it to as part of a tutorial video for a local dealership. For the most part: 100% EV (and 1,800 KWh in total) in city driving throughout the year and no gas engine start for many months. The dealership actually noted that during the oil change visit this last March.

    Here are a few pics just for giggles:

    2019-06-19 10.03.05.jpg 2019-06-19 10.03.32.jpg 2019-06-19 10.02.55.jpg 2019-06-19 10.02.11.jpg
     
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  13. DavidA

    DavidA Prius owner since July 2009

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    I'm more than 6 months in with this last tank of whatever that smelly liquid is that I bought for $2.04 a gallon, Dec. 13th, 2018. You know, for that little hatch on the other side of the car? The petrol gauge is still at more than 9/10ths full, and only because there were some more than 32 mile trips beyond EV mode into the dark side. Not once did this petrol engine thing ever start up on its own*. No maintenance mode discovered yet.

    * Winter, and some days of -26F and somewhat above that temp did start in HV mode, because, well, duh.
     
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  14. MSantos

    MSantos EcoAccelerometry

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    Thank you. Now I know I am not the only one who has not seen this mythical "maintenance mode" for many months.

    One would think it makes A LOT of sense for the ICE to start now and then, but my own experience alone does not confirm this at all. At some point, it would be nice to confirm this is a discrepancy that Toyota will either explain or fix in the near future.

    Cheers

    MSantos
     
  15. Salamander_King

    Salamander_King Senior Member

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    OK, I think I have experienced pseudo Maintenance Mode on my PRIME other day. Here is what happened.

    My daily drive is longer than EV range, so ICE comes on almost every day on it's own when EV range hit zero. However, with nice warmer days (50s in morning 70s in the afternoon), the EV range has increased steadily in last 6 weeks. Now the GOM is showing 38.0 miles which is just long enough to make the round trip for my commute all in EV. A few days ago, I was driving home in sunny afternoon with temperate close to 80F outside. The car sat in sunny parking lot all day, and the cabin temp when I got to the car after work was above 100F. It had ~50% EV SOC and the car was not charged at work.

    Even though it was bit uncomfortable at the beginning, with wide open windows I was able to tolerate near 80F temperature on my way home without turning on AC. After about 5 miles on the road, when the SOC for EV was indicating 40% and still ~15 miles EV range left, the engine started up on its own for no apparent reason. I was not accelerating quickly. There was no uphill. I did not hit HV or the defroster button or anythingelse on the dash. I was easy going 35mph on fairly flat road with no stop and go. I had no idea why the engine started but quick switch to HV and then switching back to EV shut the engine off for the rest of the way home about 10 miles. When I got home and turned off the car, I saw for the first time on my PRIME, the pop-up notice for selection of battery cooler. Well, that means the battery was somewhat overheated. In retrospect, I thought the reason the engine started on its own while driving EV with plenty of SOC left must be the way to cool down the battery. I did not have the AC on, so it would not have helped to cool down the cabin temp, but by starting the engine and shutting down the motor, the car was trying to prevent overheating battery? Do you guys think that's what happened? Have you ever experienced similar thing on your PRIME?
     
    #55 Salamander_King, Jun 20, 2019
    Last edited: Jun 20, 2019
  16. Mendel Leisk

    Mendel Leisk Senior Member

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    Hey @MSantos , good to hear from you. :)
     
  17. Tideland Prius

    Tideland Prius Moderator of the North
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    That sounds like it. It was shifting some of the burden to the engine to reduce current draw.

    Likewise. Especially about Winnipeg winters and how the Prime performs there.
     
    #57 Tideland Prius, Jun 20, 2019
    Last edited: Jun 20, 2019
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  18. MSantos

    MSantos EcoAccelerometry

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    Hi Mendel & Tideland

    Sometimes, one's gotta get in the word grind to sort out the odd concern now and then.;)

    This "maintenance mode" has been the subject of chats I've had with several Volt owners over the years, and I'll admit that I expected the Prime to be somewhat aggressive while monitoring the lack of ICE usage and forcefully fire it up on a timely basis.

    Cheers
     
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  19. Tideland Prius

    Tideland Prius Moderator of the North
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    If anyone's curious, the engine started up like a champ and I was to finally break it in (well almost.. 1,300km trip... I forgot to check the Drive Monitor but it's probably in the neighbourhood of 30% EV Drive Ratio). Highway driving allowed it to warm up properly and run lightly before heading into the mountains and getting the revs up.

    Fuel economy was insane. Trip total with 3 full charges over 1,350km was 3.4L/100km. I used a little over a tank at 47.1 litres or 12.44 US gallons.
     
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  20. jerrymildred

    jerrymildred Senior Member

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    This is a little old, but I just came across this thread. I would agree that the most likely reason the ICE came on was that the battery was getting uncomfortably warm. I haven't had that happen, but I've never driven in 80F weather with the A/C off and windows open. That always calls for air conditioning here.
     
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