1. Attachments are working again! Check out this thread for more details and to report any other bugs.

3 Failed ECUs? (2006 Prius)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by CalebW, Sep 3, 2017.

  1. CalebW

    CalebW New Member

    Joined:
    Sep 3, 2017
    6
    0
    0
    Location:
    AL
    Vehicle:
    2006 Prius
    Model:
    One
    I have recently taken my 2006 Prius to the dealership, but I'm getting some strange information from them and I think I need some advice before moving forward.

    About 6 months ago the car threw the red triangle warning light and would refuse to go into gear. After a little checking I found the the 12v battery was weak and jumping or charging the battery would allow the car to go into gear and shut off the warning light. It would do this about once a week or so, so I finally replaced the 12v battery and haven't had any issues with it for the last 6 months. . . A week ago it gave the same warning and again wouldn't go into gear, only this time the 12v is fine. I tried near everything to get it into gear but it looked like I would need to have it towed. A couple days later when I was cleaning it out before having it towed, I decided to try one more time and sure enough it went into drive! The red triangle was still on but the dealership is only a few miles from me so I drove it there.

    Now comes the part I'm struggling with. After 3 days and $450 worth of diagnostic fees they call and tell me not one, but three ECUs need to be replaced to the tune of just over $3000 (with labor). The Transmission, HV, and Power Control ECUs are all in need of replacement. As you can imagine, I was a little surprised considering how I drove the car there on its own. In my experience computer components don't "go bad." They just fail. So naturally I asked about what codes were generated to point to these three components. . . no codes. Okay sure, so they must have removed them and tested the pins. They did not. They know that these three are bad because they are not responsive. I'm fairly hopeless when it comes to most things mechanical, but I am no stranger to electronics and circuitry. Something about this doesn't feel right and I could really use some advice.

    I will concede the possibility that three computer subsystems failed simultaneously, but my biggest concern is that they don't have a clue as to why. I'm worried about putting $2000 worth of new components in if this may happen again.

    Any input someone can give will be greatly appreciated!
     
  2. Travis Decker

    Travis Decker Active Member

    Joined:
    Jul 15, 2015
    139
    115
    0
    Location:
    Portland OR
    Vehicle:
    2012 Prius
    Model:
    II
    Need to know the fault codes from techstream. We get that stuff all the time and it turns out that the car doesn't need 3 computers at the same time. Typically the dealership say something like that and then tell the customer to donate the car to charity and go into the showroom and buy a new one. If you can get the dtcs and info codes I might be able to give you a suggestion
     
    Raytheeagle likes this.
  3. CalebW

    CalebW New Member

    Joined:
    Sep 3, 2017
    6
    0
    0
    Location:
    AL
    Vehicle:
    2006 Prius
    Model:
    One
    That's really the heart of my concerns. I've asked at every chance and the dealership mechanic assures me that there are 0 codes to read. I'm highly skeptical about such an expensive diagnosis when they can't provide me with any information as to why. Also they still have the car now. I'm regretting not getting the equipment to read the codes myself before taking it in.
     
  4. hchu1

    hchu1 Active Member

    Joined:
    Sep 28, 2006
    316
    127
    0
    Location:
    Houston, Tx.
    Vehicle:
    2014 Prius v wagon
    Model:
    Two
    The dealer mechanics either don't know they are doing or they are trying to scam you. If you can get it to another dealer or someone with a techstream mini vci reader. If your ecu has issues there will be a code.
     
    Travis Decker likes this.
  5. windstrings

    windstrings Certified Prius Breeder

    Joined:
    Sep 11, 2005
    6,278
    373
    0
    Location:
    Central Texas
    Vehicle:
    2010 Prius
    Model:
    IV
    I would report them to Toyota and try another dealer "or vice versa"
     
  6. CalebW

    CalebW New Member

    Joined:
    Sep 3, 2017
    6
    0
    0
    Location:
    AL
    Vehicle:
    2006 Prius
    Model:
    One
    Thanks for all the advice! It's reassuring to know that its not just me being paranoid. I wish I hadn't shelled out $450 for them to tell me nothing, but that will be between me and their manager on Tuesday.

    Hopefully I'll be able to get it in to gear again so I can at least get it off their lot. I'll keep this thread updated as the story unfolds (and hopefully when I get the codes!)

    As an aside question looking towards the future. . . When I was in Pensacola FL, nearly every mechanic would work with my Prius no problem, but here in Auburn AL its hard to find one that will do anything more than change the oil. Should it turn out that I need to replace an ECU, would you advise against DIY? I'm pretty comfortable with vehicle and/or electrical DIY and can easily manage removing the dash, airbags, etc. However if it really is the HV ECU or something more difficult to get to then I'm not too sure.
     
  7. CalebW

    CalebW New Member

    Joined:
    Sep 3, 2017
    6
    0
    0
    Location:
    AL
    Vehicle:
    2006 Prius
    Model:
    One
    I had a meeting with the manager at the dealership this morning and was able to get some more information. I'm not sure why they had insisted that there weren't any codes generated, but the manager pulled them up and showed me and it doesn't look good. C2300, C1310, and P3102 were thrown. Since they've checked the wiring and other usual suspects it would seem that those ECUs ARE the problem! I'm still not sure why I was able to drive it though. With its history of 12v battery failure I will have them check it again, clear the codes, and see what happens after that but I think the 12v is probably fine. I'm not sure if I want to risk putting in used ECUs either.

    Any other ideas, or am I the proud owner of a large paper weight?
     
  8. Travis Decker

    Travis Decker Active Member

    Joined:
    Jul 15, 2015
    139
    115
    0
    Location:
    Portland OR
    Vehicle:
    2012 Prius
    Model:
    II
    I have seen that code posted due to the plastic in the shifter handle being loose and binding. You need to find someone qualified to diagnose the problem
     
  9. Prodigyplace

    Prodigyplace Senior Member

    Joined:
    Nov 1, 2016
    11,696
    11,317
    0
    Location:
    Central Virginia
    Vehicle:
    2017 Prius
    Model:
    Two
    I am not sure how close you are, but @bwilson4web here is a trusted Prius user. Perhaps he could help or offer suggestions.
     
  10. CalebW

    CalebW New Member

    Joined:
    Sep 3, 2017
    6
    0
    0
    Location:
    AL
    Vehicle:
    2006 Prius
    Model:
    One
    I've attached the 6 page algorithm the mechanics followed to reach their conclusions. If nothing else perhaps others will find this information useful. There seems to be some discrepancies between what they told me they did and what they actually did, but I don't think the person they had speak with me actually worked on the car himself and perhaps misspoke. I still think I don't fully understand all the parts of the flow chart though. The final step, for example, says to "Go To Relevant DTC Chart" if DTCs are output. They circled that no DTCs were output so replace all three ECUs. . . p1.jpg p2.jpg p3.jpg p4.jpg p5.jpg p6.jpg
     
  11. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    I suggest you get the car back, and plan to install three used ECUs yourself after you've confirmed the troubleshooting tree was correctly followed. Look on eBay for used ECUs. Consult techinfo.toyota.com to obtain factory repair manual info.
     
  12. Travis Decker

    Travis Decker Active Member

    Joined:
    Jul 15, 2015
    139
    115
    0
    Location:
    Portland OR
    Vehicle:
    2012 Prius
    Model:
    II
    Is your shifter notchy? There is no way from my professional experience that your car needs three computers. You have to take the Toyota engineers fault tracing procedure with a grain of salt sometimes. I'm curious what's actually wrong, but I would wager it does not need three computers. Did a north Korean neutron mini missile attack your Prius and simultaneously ruin the three computers? Could be the PCON motor, shifter, numerous things making the computer get confused. Remember this is an Atari, not a MacBook. Get a mini VCI. Scan the car with techstream and save a .tse file with freeze frame send it to me I'm glad to help you with diagnosis or do a video call and walk you through what to check on the data list. This Yelp review I got for fixing the exact same problem. Was not any computers, but this client was told the exact same thing that you were because somebody just read the diagnostic tree....... Just sayin........[​IMG]
     
  13. CalebW

    CalebW New Member

    Joined:
    Sep 3, 2017
    6
    0
    0
    Location:
    AL
    Vehicle:
    2006 Prius
    Model:
    One
    I've looked and found some good prices on replacement parts. If that's what needs to be done then I will certainly be taking that route.

    The VCI I ordered just arrived today. Unfortunately I don't think I'll be able to get the car back until this weekend. And that is a very generous offer that I will gladly accept! It may be a few days before I have more information to post, but I won't leave the forums with a cliff hanger for too long.
     
  14. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,466
    8,377
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    What part numbers do you need? I have a bunch of ecu(s) from the last car I parted out. You can try them and see if they'll fix your problem. I'm curious what's causing this issue