Gen 3 - J0V Recall - Bad MPG - ECU Swap

Discussion in 'Gen 3 Prius Main Forum' started by JonathanCWard, Sep 12, 2020.

  1. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Hey Prius Friends. I have a little story to share.

    July 2019 I took my 2013 Toyota Prius in for the Inverter Software Update Recall J0V. The car at the time had 209,000 miles on it and averaged 43 miles per gallon. The recall was performed by Hollywood Toyota and picked up a few hours later.

    After getting the car back I realized my fuel economy was not the same. I thought, the car needs to adapt due to the ECU being updated and will relearn my driving. A week or so later I realize nothing has changed. I’m getting 32/33 average and can not seem to get it back in the 40’s.

    I started doing some research and found I was not the only one with this issue. Thinking there is little chance it could be the recall update, I decided to look further into some maintenance that I should perform that has not yet been done. I removed and cleaned the: Intake manifold, EGR system, Throttle body, Mass Airflow Sensor, Injectors. I removed and replaced the PCV Valve, Spark Plugs, Air filters. I may be missing a thing or two. Because I had heard of a stuck caliper pin causing a mileage reduction, I decided to remove and replace the front brakes, rotors, and lube the pins. Removed the read tire, lubed the rear caliper pins.

    Throughout these different things performed on the car from January 2020 til a month or so ago (August) still no change. 32mpg is the somewhat new average. Over a year of 32mpg average.

    Late August I took the car back to Hollywood Toyota and had a health check performed. A couple hours later the service manager and tech shared with me that the car checked out fine and they found nothing wrong. So on September 8th I took the car to Claremont Toyota and had a health check performed. A couple hours later, I received the same info. Nothing found, can’t seem to find a reason as to why it would not be performing at the previous average which it had for two years of me owning it prior to the recall.

    Yesterday, after a decent amount of research I decided to move to pretty much the only next step I can think of. While Toyota can not revert or remove the update, taking it back to the previous state of software, I can remove the software from my car by removing the ECU all together and swapping it with one I know has not received the recall update. I found one online and ordered it after speaking with the company, running the VIN to confirm the recall was still open and not performed. This is where I currently am in the story. It arrives in a few days, I will swap it out, and update this thread on what the results are after putting some miles on it. Feel free to chime in, share your experience if similar, or any constructive advice you might have.

    Part Number for ECU: 89660-47514
     
    Pluggo likes this.
  2. NewHybridOwner

    NewHybridOwner Active Member

    Joined:
    Nov 21, 2018
    411
    200
    0
    Location:
    W. Michigan
    Vehicle:
    2015 Prius
    Model:
    Four
    I thought that that update (like the more recent one that applied to vehicles that had not had the earlier one done) was supposed to remedy the situation where the vehicles could simply die altogether instead of switching to some kind of limp-home mode if ... (perhaps it was if the inverter electronics started overheating). There were reported cases of Priuses losing all power while driving in the fast lane on SoCal freeways -- not something that I would want to happen.
    Is it possible to simply unplug one ECU and install another, or do they have to be "matched" to the rest of the electronics -- probably using TechStream?
    And when it comes time to sell the car, a VIN check will show that the update -- this is a Safety Recall, keep in mind, and if I understand correctly, the vehicle registration cannot be renewed in CA if the update has not been performed -- has been performed on this vehicle, but you have reversed that update. And how will a new owner get the update done again for free, when the vehicle records shows that it has already been done?

    I think you should reconsider carefully what you are proposing to do.
     
    JonathanCWard likes this.
  3. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Hey there. Great questions. My response will be brief as I have to head out for a bit. ECU does not have to be matched. You can do a swap, then reset the immobilizer by jumping the 4 and 13 pin for 30 minutes in ACC-on mode. This will pair the ecu to car. The VIN will still be the previous VIN and may be updated in the future if desired. As for resale, or registration I’m not concerned there as my first (2005) and third (2013) Prius were totaled, one with 291,000 miles and the other with 152,000 miles. My second (2008) I gave to my parents with 164,000 miles still going strong.

    If I wanted to have the recall performed on the ecu I am installing it would be no problem having it performed. As for the recall in general, I have driven my first 2013 162,000 miles with no issues, and this one 209,000 until the recall was performed. I’ll take my very slim chance of it stalling (while I am curious how many this has actually happened to) than getting 10 miles less per gallon.

    Thank you for your concern, but I do plan to move forward with trying to locate this issue. Toyota dealerships can not locate the issue and Toyota Corporate has taken all my notes and informed me that they do not have anything in place to address this concern and are no help to me at this time. They recommend to continue to deal with dealers, which I have found to be useless over my 12 years of owning Prius’ as it is.

    (Previously I was a Sales Manager of a Toyota dealership and would say the same thing then too.).
     
  4. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    3,877
    3,059
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    Got my smog check & registration renewed last month without the update, I live in commie-fornia.
     
    JonathanCWard likes this.
  5. royrose

    royrose Senior Member

    Joined:
    Mar 21, 2009
    1,026
    637
    4
    Location:
    Foot of Pikes Peak
    Vehicle:
    2010 Prius
    Model:
    IV
    I understand how you came to checking out this possibility but what about those of us who have had the recall and haven't had a drop in mpg? Maybe the timing of the drop in mpg is a coincidence and caused by something else.

    Your hybrid battery may check out as "OK" at the dealer but still have not much reserve left. Have you checked the hybrid battery health with the Dr. Prius app?
     
  6. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Hi. Which is why I decided to do the crap ton of maintenance I did to see if it was caused by something other than the recall. While I’m not the only one with the issue right after the recall I’d believe it is the recall. No luck with everything performed.

    I did run a Dr. Prius battery check maybe 6 months ago (approx 6-7 months after recall was performed) and hybrid battery checked out fine. Considered that as a possibility however seems with dealer check and Dr. Prius it is fine. Before I touch the hybrid battery or 12V I plan to change ecu. If my mileage comes back after the swap, we know it is not anything battery related. If it does not, then it could potentially be 12V or HV battery related.
     
  7. Johnny Cakes

    Johnny Cakes Senior Member

    Joined:
    Dec 30, 2016
    646
    518
    2
    Location:
    Washington, D.C.
    Vehicle:
    2015 Prius
    Model:
    Five
    This is probably not the answer you are looking for, but you already have 200,000 miles on your car. The average price per gallon in Los Angeles is $3.77. For every 10,000 miles you drive, the difference in fuel cost from what your MPG is versus what you want it to be is $266.

    You've gone to two different dealerships in a month. You've:
    and now you have purchased a new ECU and will install it when it arrives, despite possible safety concerns.

    I'd recommend taking a step back and thinking about cost versus reward -- whether your time and money is well spent on this issue, given the miles on the car and the possibility (or maybe probability) that you will never find a solution.

    Whatever you decide to do, I wish you luck.
     
    JonathanCWard likes this.
  8. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Thanks for doing some math for me.

    The ecu cost me $150. If it fixes the issue, it’s well worth the headache on my end. All the other things I did as I have done all the maintenance was simply things that needed to be performed anyway.

    Obviously if I had paid a shop to do all of this it may not have been worth the cost. As for the two dealerships, there was no cost involved.

    I appreciate and respect your response. I have thought it out, nearly all the variables, and find it to be worth it at this time. I will update you as to whether this is the fix. If so, I’d imagine many others would have interest in doing the same.

    For the safety concern... back to my earlier post... just how many have experienced said safety concern for it to truly be a safety concern. VW had some major issues lately and unfortunately that changed everything when it comes to recall and safety type issues.
     
    Johnny Cakes likes this.
  9. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    By the way, I should mention. I have followed you for years on here (even though I just created an account) and have appreciated your responses over the years on people’s post.
    Thank you for taking the time.
     
    Johnny Cakes likes this.
  10. StarCaller

    StarCaller Senior Member

    Joined:
    Feb 15, 2014
    1,064
    571
    0
    Location:
    Cedar Crest, NM, USA
    Vehicle:
    2014 Prius
    Model:
    Two
    are you sure about that?

    edit: pin 4 & 13 would be in the obd plug, right?
     
    #10 StarCaller, Sep 12, 2020
    Last edited: Sep 12, 2020
  11. Majafamily

    Majafamily Junior Member

    Joined:
    Feb 19, 2020
    49
    26
    0
    Location:
    Elk Grove, CA
    Vehicle:
    2015 Prius
    Model:
    ----USA----
    Nothing to really add, but have you checked your cars electrical system? Maybe a low battery or other components? That's my guess. Engine burning more to try and charge batteries but there's an issue somewhere along the way.
     
  12. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    That is correct. 4 and 13 in the orb plug.

    Put in a jumper.
    Turn car to ACC-on (by pressing button twice)
    Leave for 30 minutes.
    Turn car off
    Remove jumper
    Start car normally.
     
    StarCaller likes this.
  13. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Yeah. Toyota checked the system, as well as my own test ran through Dr. Prius. Agreed. The engine is running more and longer, hence the issue. This is also unfortunately what the recall does as well. Limits the inverter output which causes more strain and use on the gas engine. (Per the Toyota tech and reading into it) .
     
  14. ASRDogman

    ASRDogman Senior Member

    Joined:
    May 29, 2018
    2,486
    1,610
    0
    Location:
    Indian River County, Florida
    Vehicle:
    2010 Prius
    Model:
    Two
    "The ecu cost me $150. If it fixes the issue,"
    I don't believe this will "fix" your issue. Most people seem to report their mileage has dropped after
    the recall, but after driving a while it comes back. NO, not everyone, but just going by the ones who
    have commented in Prius Chat.

    WHY did you what a whole year before taking the car back? You should have taken it back a lot sooner.

    The reason for the recall was because it could cause the car to shut off and leave the driver stranded in
    the middle of a busy road potentially causing a wreck where they and/or others could get hurt or killed.
    We may not agree with the solution Toyota came up with, and we pay the price with more fuel cost,
    but at least you won't won't end up injured or dead.

    I think it is a temporary "fix" I think, And if EVERY Prius driver would complain, Toyota would probably
    come up with a solution to the problem. Just to save face. Maybe not, but you don't know unless you try.
     
    JonathanCWard likes this.
  15. royrose

    royrose Senior Member

    Joined:
    Mar 21, 2009
    1,026
    637
    4
    Location:
    Foot of Pikes Peak
    Vehicle:
    2010 Prius
    Model:
    IV
    How about this possibility: The recall is a software update that alters the management of the inverter. Maybe some inverters, while still functioning, are (to use a highly technical term) partially fried and therefore are more affected by the update than others. So, maybe going back to a non updated ecu will restore functioning, maybe not. If not, maybe putting in a different (used) inverter would help.

    Trouble is PriusChat doesn't provide an accurate sample. People come here with problems. Many more who don't come here may be doing fine (or may have a drop in mpg and don't pay attention to it). So, we just don't know whether most have a drop in mpg.

    Jonathan, once you are done you should be certified as a Toyota Hybrid master mechanic.
     
  16. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Thanks for the little compliment. I will say, 12 years of owning these cars and doing my own maintenance for the most part, you could ask a question about these cars and I could most likely answer it. All the way down to what size bolt is where. ‍

    What I have not had to venture much into is the electrical management system.

    I agree with you. There are far more with this issue just not speaking out about it or knowing where to do so. I posted this in the Toyota Prius Owners Group in FB for those who may be having the issue to keep them informed and found there is another who spoke up with a loss of MPG after the recall.

    A commenter just above mentioned that others found their mileage came back shortly after the recall was done and why I waited so long (basically a year) to take it back to have tested. Little did I know it could be the recall, even after knowing the mileage plummeted after receiving the car back from the dealer. So I did as mentioned above and started doing other maintenance which the car would need anyway to get it back. Wednesday or so can not get here soon enough.

    I’ve done basically everything except:
    Replace either battery, Replace Mass Air Flow Sensor (has been cleaned), Flush transmission fluid, flush radiator fluid, replace inverter/motor/or anything involved with these electronically. I think that’s about it. I’ve literally removed nearly everything and cleaned and put it back on in an attempt. That damn EGR. Still thinking back to how clogged they get. For those who have not pulled and cleaned yours... if you are anywhere close to or over 100k on yours, it’s beyond needed. Do it! And be patient, and change your spark plugs while you’re at it since you have to remove the windshield wiper assembly to get to either of these and perform the maintenance.

    That’s all for now.
     
    #16 JonathanCWard, Sep 13, 2020
    Last edited: Sep 13, 2020
  17. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,946
    7,311
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Is that the part number you ordered? That's an ECM. The ECM isn't reflashed or touched in this recall.

    In this recall, the Power Management Control ECU will be reflashed (always), along with the MG ECU (if recall E0E had not previously been done).
     
    JonathanCWard likes this.
  18. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Per Toyota, this ECU is described as...

    “Computer, Engine Control. Engine Control Unit. Powertrain Control Module.
    A module in a vehicle used to monitor and control many components of the vehicle's engine management system”

    I have the Toyota maintenance printout for the recall that the tech would receive. Looking through it again now.
     
  19. JonathanCWard

    JonathanCWard New Member

    Joined:
    Sep 8, 2020
    11
    4
    0
    Location:
    Los Angeles
    Vehicle:
    2013 Prius
    Model:
    Persona
    Based on your experience following this issue for a couple years on here. If it is correct that this is not the correct part and does not fix the issue, what parts should be replaced if the idea is to remove the software update from the car by removing the part.

    What is your advice knowing what you have read in the past, and in my post?
     
  20. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    9,946
    7,311
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    I should think you would want to replace the Power Management Control ECU (located in the ECU village behind the glove box) and the MG ECU (inside the inverter assembly). If you happen to know whether the car had already had E0E done or not, or if you noted your calibration numbers before going in for the recall so as to see which ones are different now, you could refine that some.

    If anything reflashed has a discernible effect on MPG (of which I am not convinced), I would expect it's more likely to be the MG ECU updates than the J0V change to the power management control ECU.

    I don't know your background; for about the same money, you might be able to acquire a resource that would help with a plan to realistically assess how well your suspicions about the recall are supported by your data, as well as what data you would need to collect, and how, to draw reliable conclusions from the sort of experiment you have in mind. That might be an investment with a better long-term payoff.
     
Loading...