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Battery level not moving in drive

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Violet martin, May 5, 2021.

  1. Violet martin

    Violet martin New Member

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    I have a 2014 Prius. Bought it brand new never had an issue until now. Recently was getting fumes in the car and a gurgling noise, good news is that Toyota fixed the issue replacing manifold assembly, intake, gaskets, compression spring and EGR pipe. The fumes and gurgling noise were resolved, HOWEVER, now I’m getting horrible MPG. Went from 50-55mpg to 35mpg!!! Toyota doesn’t know why. Only thing I’ve noticed it that the battery level no longer moves up and down while driving the car, it will if parked but not in drive.
     
  2. bisco

    bisco cookie crumbler

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    welcome!
    they need to address that. maybe they left something unplugged. what does it do when parked?

    where is the level stuck when driving? full? low? in between?
     
  3. Violet martin

    Violet martin New Member

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    When in park it seems to be charging and using the battery (bars go down and engine will eventually kick in and bars go back up) but I think even that is way off from what it was. When in drive though it will stay stuck at whatever level the battery was in when it was in park. And I’ve been doing two hour drives lately too and that battery doesn’t even move up or down a bar, nothing. I have an appointment with Toyota dealer next month and I called Toyota corporate too. They said I have to continue to drive it like this for a month so they can study the data to try to narrow down what’s wrong because they are clueless at this point why I went from getting 50+ mpg to getting 35mpg now after all the work they just did to the car. ‍♀️
     
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  4. bisco

    bisco cookie crumbler

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    best to track mpg by the tank. otherwise, you can be prone to emotional mistakes based on observation
     
  5. jerrymildred

    jerrymildred Senior Member

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    Your observations are too extreme to be imaginary. I would take it back to the dealer and insist that they fix what they broke. The basics steps when you work on something and the work causes a malfunction begin with going back over everything you touched or even came close to and making sure it's all as it should be.

    "Drive it for a month while they study the data" sounds like they are hoping the problem will resolve itself or you'll get used to getting lousy gas mileage.
     
    #5 jerrymildred, May 6, 2021
    Last edited: May 6, 2021
  6. Grit

    Grit Senior Member

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    or stay logged onto nerflix and worry more about the new series then priority of car is not on the todo list.
     
  7. Violet martin

    Violet martin New Member

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    I have been as well because at first I thought maybe it’s a computer issue, but computing my own mpg it confirms the lousy mileage the car is tracking. Plus I’m filling up twice as much as before too so I’m not sure how anyone would be able to ignore this much of a mpg drop. Crazy! Toyota set me up with a loaner car until they figure out what they screwed up that’s causing this.
     
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  8. jerrymildred

    jerrymildred Senior Member

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    I hope you're not still driving that loaner car.
     
  9. Violet martin

    Violet martin New Member

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    They gave me my Prius back after 2 weeks in a loaner and they told me they can’t figure out why this is happening. Since then it’s been a battle to get them to have their regional hybrid specialist contact me.
     
  10. jerrymildred

    jerrymildred Senior Member

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    Wow! That's crazy.
     
  11. Grit

    Grit Senior Member

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    that usually means they’re thinking that you will make multiple phone calls to reach out to their specialist because it’s your issue and not theirs.
     
  12. TheLastMojojomo

    TheLastMojojomo Active Member

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    There is a possible explanation for your low mpg's and nothing may be wrong.

    I have been working on a comprehensive post about a low mpg mechanism that nobody knows about. It can explain many cases of phantom mpg loss with seemingly no reason. I will share a portion of this comprehensive post shortly.

    I know you have had a lot of work done on the car, but if nothing is found to be wrong, and your 12v was disconnected during the repairs, this low mpg mechanism could be the possible reason for your problems.

    The text below is copy and pasted from this Reddit Post: Any ideas about why I am only getting about 35MPG? (More info in the comments). The info I gave to the OP about the low mpg mechansim has apparently solved his phantom low mpg issues.

    The final post is still a work in progress.

    Here we go:

    Is your driving mostly at city speeds under 40 mph?

    I have a Post on PriusChat that describes a low mpg mechanism basically nobody knows about.

    I'm currently working on a more comprehensive post with data evidence of this mechanism.

    Basically what happens is on the Gen 2 Prius (it also applies to other generations I think) the Prius needs to relearn parameters for the Hybrid Control ECU after a 12v disconnect or ECU memory reset. The relearn procedure is not just based on driving and actually has to do with a certain commute style. If you don't do this commute style to get the Hybrid Control ECU to relearn, the Prius will become locked in this unlearned state for EV mode potentially forever and drastically effect city mpgs by 5-15 miles per gallon...

    I have a way to test if your Prius is in this low mpg state if you're interested in that... let me know and I'll get you that info. I could use a test subject for further proof of this mechanism...

    This may or may not be what's causing your low mpg as there are so many factors, but I'll copy and paste several paragraphs from the comprehensive post I'm working on that describes this mechanism in more detail and my low mpg experience:

    What are the signs and symptoms of a Hybrid Control ECU that is not at peak parameters compared to one that is? Let me start by saying total power is not effected. If you floored the gas pedal, the ICE, MG1, and MG2 work together to provide as much power to the wheels as quickly as possible. In either ECU state, hard acceleration will be the same. The main differentiation occurs with how much acceleration, speed, and distance, is allowed in pure EV mode at various HV Battery State Of Charges before the ICE spins up to supplement EV power. This occurs mainly at city speeds between 0-40 mph. Highway mpg's are marginally effected.

    In an UNLEARNED ECU state Prius, EV mode capabilities are a fraction of the learned ECU's capabilities. Pure EV mode is still possible with excedingly light pedal pressure, but you have to accelerate VERY slowly. It makes it very unrealistic to stay in EV mode and drive normally the majority of the time in the city traffic, even at full green bars. The Prius refuses to discharge the HV Battery aggressively through pure EV mode in any circumstance. Once the HV Batt SOC drops below the first blue bar, the ICE kicks on almost immediately with any amount of pedal pressure. It becomes impossible to use EV mode by itself unless your at a slow crawl.

    In the LEARNED ECU state, you get much more acceleration, speed, and pedal travel in EV mode on a much lower HV Batt SOC. EV mode is able to be used aggressively. Easily clearing a mile or more and are able to keep up with the stop and go traffic, accelerating and decelerating completely normally without the ICE kicking on down to 4 blue HV SOC bars. In most situations, you get about 2-4x the pedal travel/acceleration in pure EV mode before the ICE spins up compared to the UNLEARNED state. However, once SOC drops below 4 blue bars in the LEARNED state, that's when EV mode will really begin to struggle in normal city traffic and all bets are off as to pure EV mode operation. In my experience, even at 4 blue SOC bars in a LEARNED ECU, you get roughly the same if not more power in EV mode than you would at FULL green bars in an UNLEARNED ECU. That's how drastic the difference is, and why city mpg's are generally effected by 10 or more mpg.

    What is the commute style for the Hybrid Control ECU to relearn? I couldn't tell you 100% for sure in no uncertain terms what the exact commute style is. But I have a general idea of what's required. It seems that a period of interstate driving at 65+ mph, possibly with cruise control on, done multiple times a day like a 9-5 commute, done for 2-3 days in a row is required to initiate relearn. I must stress I'm not 100% sure on the exacts of the commute style required. This was just the commute style that reverted my ECU back to the LEARNED state . Once my ECU relearned, it stayed in the LEARNED state no matter how or where I drove.

    My Prius spent over 1.5 years and 10,000+ miles of driving in the UNLEARNED ECU state. My city mpg's and EV power suddenly shot back up to high levels after being weak for so long and the only thing that changed was I undertook a commute style similar to what's described above. I also replicated this multiple times after a battery disconnect, losing EV mode power until I did that same commute for a couple days. In my low mpg story post, I explain the exact events/timeline that led up to this discovery and why I think my Prius spent so long in the UNLEARNED state. You'll find I'm uniquely qualified for this due to how I use my Prius for mail delivery at the USPS. Going from the UNLEARNED state to the LEARNED state made my mail route and city mpg's jump from 35 to 45+ thanks to the extra EV power.

    I knew something was immediately different. My pedal travel and power in EV mode drastically increased, and so did my mpg's. I crushed my previous R001 mpg record of 44 mpg and got around 48 mpg. And not only did I crush it once. I crushed it multiple days in a row. I would almost always from this point forward get 43-47 mpg on R001 in the summer after never getting over 39 on my best day and rarely above 35 for a year and a half. Doing R001 that's 106 miles and 400 stops really gives you a feel for the Hybrid System. You start and stop in the exact same places, virtually in the exact same ways, 400 times a day... day after day. It was very easy to feel and measure how the Hybrid System function had changed on various portions of the route. I was able to clear whole blocks and dead end roads in EV mode that I couldn't before. The improvements were permanent and did not falter once no matter how I drove. General city mpg's improved permanently and dramatically as well.

    I figured out my commute was the cause.

    So what was the commute change?

    I started loaning myself out to another office for work, starting in July 2019. This time I started going to Mount Horeb, WI. This commute was about 10 minutes of city driving (0-40mph) 15 minutes of highway driving (55-65 mph) and 25 minutes of interstate driving (65-75 mph). I did this commute 1-3 days a week often consecutively for the next 6 months.

    THIS WAS THE ONLY THING THAT CHANGED.

    To prove my 12v disconnect ECU reset theory further, I disconnected my battery twice during the 6 months of making this commute. Once to do a piston soak and again to do a 12v battery check as I thought maybe my 12v was the root of the problem afterall. But nope. The first several days after I disconnected it, my EV mode lost it's power and reverted back to the WEAK EV mode state. My mpg's dropped on R001 down to 35 again and the Hybrid System responded exactly like it did for the 1.5 years it was in the WEAK EV state. When I did the commute to Mount Horeb a couple consecutive times later, EV power was back in business. 10+ mpg jump and a lot more pedal travel in EV. I replicated this twice.

    Unfortunately my mpg's did not maintain forever.

    In early 2020 I had my passenger side Wheel Bearing and CV Axel go bad. I disconnected my battery for this repair. All my EV mode power and mpg's again disappeared. I have since not regained my mpg's. Why is this? Because my commute changed again.

    Due to life circumstances creeping back in, I stopped working in Mount Horeb and other Post Offices besides my hometown at the exact same time I replaced my CV Axel/Wheel Bearing. This meant back to no consistent commute with interstate driving anywhere other than the occasional trip. My mpg's and EV mode power tanked back down to the 30-35 mpg range on R001 and have remained that way ever since. My commute style has not changed either.

    As of June 23rd, 2021 and 13,000 miles later, my Hybrid ECU is still in the WEAK EV state from the last 12v disconnect. I'm still in similar life circumstances that prevent me from having a commute for work that would initiate my relearn theory.

    I've also found several other posts on PriusChat that describe this exact low mpg phenomenon of the ICE spinning up quickly with little pedal travel resulting in low mpg's. They sound eerily similar to all I've described above. These posts are below:

    First, here is a different post I made a few months ago describing what I described here, just not as fleshed out. https://priuschat.com/index.php?threads/221332/

    Here are the other posts I found that sound very similar to my low mpg mechanism:

    https://priuschat.com/threads/beware-of-dealer-ecu-calibration-mpg-way-down.7470/

    https://priuschat.com/threads/2007-poor-gas-mileage.89688/

    ***https://priuschat.com/index.php?posts/56928 ***

    Here is one from a Prius v. The OP literally went crazy trying to find what was causing his low mpg phenomenon on multiple Prii but never did. The mechanism of low mpg sounds exactly like what I describe but on the Gen 3 Prius drivetrain.

    https://priuschat.com/threads/engine-almost-always-running.207569/

    Like I said the commute style required to initiate RELEARN is not straightforward, but fairly simple once the right parameters are met. I'll copy and paste exactly what I've tried and what I think triggers the LEARNED state below. But again I'm not sure.

    I'll edit in that info below here. Give me a few minutes.

    EDIT:

    However, I'm in the middle stages of taking the time to narrow down what commute initiates FULL EV mode. I've been spending the time I can by driving different route styles over the course of multiple days that I theorize will initiate the RELEARN process for FULL EV MODE. So far to my surprise, I have not been able to get the ECU to initiate FULL EV MODE.

    I have done 2 different commute styles, 3 days each. One commute in the morning, one at night. I made the commute round trip each time, so it started at home and ended at home both times. There was no drive to my destination, park, then drive back later. It was one big circle of a trip, twice a day, once in the morning, once in the evening for 3 days to see if I could initiate FULL EV MODE.

    First commute was to the town of my old warehouse job for 3 days twice a day. About 50 miles each trip so 100 miles a day. It had about 20 minutes of interstate driving at 70+ mph for each morning and evening trip made. My ECU did not relearn.

    Second commute was to Mount Horeb, WI, almost the same commute that initiated relearn just without a pause. I did 84 miles twice day for a total of about 170 miles driven per day. The difference was I drove there round trip twice a day rather than park, work for 8-10 hours, then leave and come home for only one round trip. So twice the mileage in a day compared to the original Mount Horeb commute that initiated FULL EV MODE. There was about an hour of interstate driving at 70+ mph for each trip. So 2 hours of interstate driving a day. To my frustration, the FULL EV MODE didn't initiate. I thoroughly expected this to work. There seems to be more to it than just driving all over the place. It honestly makes me think there is some simple, but specific parameter that needs to be satisfied for the ECU to initiate FULL EV MODE. What that is I don't know. All I can do is theorize because I'm never going to be able get a straight answer.

    From the point you get off the interstate to the Mount Horeb Post Office is less than 5 minutes. Maybe there's a condition that is satisfied in the computers with immediate shutdown after a certain period of getting off the interstate and into the city. My hometown to the interstate in all directions is 20+ minutes so it could explain why doing the commutes round trip didn't work, despite taking a break in between. I took at least an 8 hour break when doing the round trip commutes twice a day to simulate what would happen when I'd go to Mount Horeb one way. The interstate driving at 70+ mph has to be important because no other commute without it has initiated the FULL EV MODE state. But in the end really I don't have a clue.

    All I know is the original commute when working in Mount Horeb initiated FULL EV MODE multiple times between 1 and 2 days of that commute. And still likely initiates FULL EV MODE. I really didn't do anything special besides drive their, park and shut the car off for 8-10 hours and then drive back. Now driving there round trip twice a day for 3 days did nothing to initiate FULL EV MODE. There may be something with the shutdown interval related to the interstate driving. That's my best guess as of now.

    Also I'm going to give you the data in this comment for how to test scientifically that your Prius ECU is in the LEARNED or UNLEARNED state. It's really not that hard.

    This info is supposed to be a part of my future post that will have graphs and data to back it up....I think I'll try and get the graph screenshots in with an Imgur post.

    This part is still a work in progress so it's not as fleshed out as will be in the end.

    Testing and Evidence
    How do you determine scientifically that your Hybrid Control ECU is in the LEARNED or UNLEARNED state? All you need to do is measure the percentage of gas pedal travel that is allowed while traveling in EV Mode at city speeds before the ICE kicks on. The amount of pedal travel allowed before ICE operation will show whether you have a LEARNED or UNLEARNED ECU. More pedal travel in EV mode being the LEARNED state, and less pedal travel being the UNLEARNED state.

    Note going forward, pedal travel will also be referred to as Accelerator Pedal Angle due to it being the measurement term. I will use them interchangeably.

    These tests were done using a Bluetooth Code Reader, Smartphone, Torque App, and the Realtime Charts add on for Torque. I'll explain how I did the tests after I convey the evidence.

    UNLEARNED ECU State Evidence and Testing:
    Pedal Angles are much lower in the UNLEARNED ECU state for EV mode. When the HV Battery SOC is between 5-8 bars on the display, Accelerator Pedal Angle is limited to between 28-35% of max before the ICE kicks on when traveling between 10-40 mph. The max pedal angle for EV mode is allowed to be slightly higher at 40-50% when accelerating between 0 and 10mph. It also varies with SOC. Foe example, 7 bars of charge will be closer to the 35% pedal angle, while 5 bars will be closer to 28%, etc.

    This whole next section should be read using This Imgur Post.. All the text that leads up the next paragraph is in the Imgur post.

    LEARNED ECU Evidence and Testing
    Pedal Angle and MG2 Torque are much higher for EV mode in a LEARNED ECU state. The problem is I haven't been able to measure the LEARNED ECU state because my Prius has been in the UNLEARNED state for the past 1.5 years. I still have not been able to reinitiate the LEARNED ECU state, even with trying experimental commutes. This is explained more in my Prius story that I talked about above. I was hoping I'd have clear cut and dry evidence of a LEARNED vs UNLEARNED ECU but I have not been able to do the correct commute to initiate RELEARN due to life circumstances. I'm becoming more confused as to what the exact pathology to this phenomenon is because it just doesn't seem to make sense. It clearly isn't related to just driving alone. Something needs to be done specifically commute wise to initiate RELEARN, I just don't know exactly what it is. Who knows, maybe there is some sort of phantom problem with my Prius that I just haven't identified.

    But I will need you guys to test your Prii so we can gather data. I have shown what the UNLEARNED state is, I'll need test data from you guys to prove the LEARNED state.

    Testing
    I will list multiple ways to do these tests.

    For my method you will need:

    1.) An Android Smartphone

    • (Apple users skip these steps, alternative method below)
    2.) A OBDII Bluetooth Code Reader to connect to your Smartphone

    3.) Torque Pro App

    • To get access to these Prius sensors you'll have to add the Custom Prius PID's in the settings.
    4.) Realtime Charts add on for Torque.

    Apple/Alternative Method:

    For the alternative method you will need:

    1.) Apple/Android Smartphone

    2.) A WiFi OBDII Code Reader or a more expensive Bluetooth OBDII Code Reader due to iOS using different Bluetooth. Android users can still use the cheap Bluetooth Code Reader

    3.) A compatible free or paid OBDII scanning app that allows you to create graphs or display sensor data similar to the Torque screenshot below.

    You will need to add the Prius specific OBDII PID'S to whatever app your using. There should be an option for this in the settings if the app is reputable. You will need to find out how to setup the sensors/data yourself.

    Assuming you have a smartphone, all of this will cost about $20.

    It will take some fiddling around to get the settings exactly how you want them, I'm not going to explain step by step how to do it as that will take to long.

    Setup the Realtime Charts or sensor layout similar to the posts above so you're at the very least recording speed, HV Batt SOC, Accelerator Pedal Angle, and engine RPMs.

    For Realtime Charts you'll want the sampling rate at at least 250ms so it records the sensor data 4 times a second if possible. This will give you a more accurate play by play of when the ICE activates compared to the Accelerator Pedal Angle. I would recommend putting the MG2 Torque sensor in as well to record the EV mode Accelerator Pedal relationship.

    If your Accelerator Pedal Angle is allowed to go significantly above 35% while above 10mph in EV mode, your Prius is in the LEARNED state.

    If your Prius ICE kicks on around and below the 35% threshold, you're in the UNLEARNED state.

    It's as simple as that.

    If you guys made it this far, thanks for reading and hopefully together we can discover a unknown cause of low mpg. Test away and help me prove my theory!

    Thanks guys!!!
     
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  13. ChapmanF

    ChapmanF Senior Member

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    An interesting theory. Have you looked in the Repair Manual (more info) for the "Confirmation Driving Pattern" associated with traction battery condition DTCs like P0A80?

    (I'm not sure the Gen 2 repair manual even gives a "confirmation driving pattern" for P0A80. The Gen 3 manual definitely does, though there are also threads about the description maybe not being quite complete, which is something I have run into myself with a different code.)

    The idea of OBD monitors that are cleared and require certain preconditions to complete again sounds tantalizingly close to what you're speculating about.
     
  14. TheLastMojojomo

    TheLastMojojomo Active Member

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    Chapman I think you're onto something.

    Looking into how confirmation driving patterns and clearing permanent DTC's work (mostly thanks to your reply ), it makes perfect sense.

    Permanent DTC's.jpg

    It took me 3 consecutive trips back to back to back to get my Prius back into the LEARNED State doing the commute that I did. I did nothing but purely that commute for multiple days in a row.

    Maybe there is some sort of "Phantom Confirmation Driving Pattern" for one of the ECU's when it loses it's memory after a 12v disconnect. But what is it and what exactly do I need to do? That's the question.

    I checked my owners manual and nothing stood out but will have to look more thoroughly again.

    My Prius is still in what I call the UNLEARNED State after 18,000 miles now. I'm going to try to replicate the exact conditions of the commute that initiated me into the LEARNED State in the past, 3 consecutive times in a row and see if I can finally get back to 45+ mpg's in the city.

    Thanks for the info!
     
  15. ChapmanF

    ChapmanF Senior Member

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    I notice your screenshot there is a Techstream screen.

    I've noticed there is some information on how permanent codes and confirmation patterns work that's in help screens in Techstream, but there's a lot more in the repair manual. Each different permanent code can have a confirmation driving pattern specific just to that code, which makes sense, so the driving will cover whatever conditions have to be checked for that monitor.

    I'm also pretty sure I've noticed points where the info in the manual and the help screens in Techstream said different things. My hunch is the manual is more likely to be right when that happens; I think the help screen information in Techstream is more generic, and maybe hasn't even been reviewed much over the years.

    I have even run into one case where the pattern in the manual wasn't right; I had a permanent P0102 ECM code for something like a year, and it drove me crazy, because I went through every step of that pattern some crazy number of times and I was sure I hadn't missed any. Elektroingenieur looked up the same code in a later repair manual edition and found out, yeah, there was a step in the confirmation pattern left out of the edition I was looking at.
     
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  16. TheLastMojojomo

    TheLastMojojomo Active Member

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    Well now I'm at a loss.

    I did virtually the exact same commute that originally put my Prius in the LEARNED state for one week straight and nothing changed.

    There has to be something specific that triggers the change in the computers. But what is it?

    The only thing that was different at the time the commute triggered the LEARNED state was I had 205/55/R16 tires on instead of the OEM Touring size of 195/55/R16. And it was possibly a bit warmer due to it being during the Summer months.

    At this point I think I'm just going to do a write up of the UNLEARNED state and let other Prius owners test their Prii to showcase the LEARNED state to hopefully make my point for me.

    These posts below prove that others have had this exact problem I'm experiencing so I know I'm not an isolated incident:

    Beware of Dealer ECU Calibration MPG way down

    2007 "poor" gas mileage

    Significant reduction in MPG between 2004 and 2005 Prius'

    Here is one from a Prius v: Possible undiscovered performance and MPG issues with Prius v (lowercase v)

    Posted via the PriusChat mobile app.