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2004 Prius Error Code Help!

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by darkgiant, Sep 15, 2015.

  1. darkgiant

    darkgiant Member

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    Hello!

    I had posted here about issues I am experiencing with my key fobs on my current 2004 Prius. The issue is that I am unable to unlock and lock the car via the SKS Remote, and I am only able to turn on the car via inputting one of the fobs into the slot to turn on the car.

    I had visited the Toyota Dealer and also tried my VCI cable to get more details to resolving the issue. Originally the dealership diagnosed this as a reprogramming issue, quoting me $118 plus tax. Instead, they found out that the "Smart Key ECU to Immobilizer has a communication failure, thus error B2775".

    They quoted 3-4 hours to figure out what the issue could be (with an hourly rate of $118 per hour). I don't have all that money with me, and the car drives great, and gets great gas mileage. Would love to get any help on here as I personally dislike visiting dealers.

    I have attached a full list of error codes I originally received when I plugged in my VCI cable and used the Techstream software, would love solutions and help on diagnosing these codes, and figuring out how to get the key fobs working again.

    As a comment, I purchased this car few months ago for a good price, the car itself just topped 130,000 miles as of Saturday.

     
  2. ChapmanF

    ChapmanF Senior Member

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    Access to the service manuals on techinfo.toyota.com is a lot cheaper than that. :) It seems like this might be the sort of problem that could be a challenge to get to the bottom of if you're trying to do it without the best information you can get. You could hit the jackpot here if somebody else happens to have had an exactly matching problem ... you could also get sidetracked, if somebody else had a problem that seemed really similar but, at bottom, wasn't ....

    -Chap
     
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I agree that you need access to techinfo so that you can follow the troubleshooting advice for B2775. This involves trying to register the ECU communications ID. If that doesn't work then the transponder key ECU would need to be replaced.

    Since this was a recent used car purchase, who knows what was the prior service history, whether the fobs you have were properly registered to the car, etc. You will need to carefully follow the troubleshooting advice and could easily spend several hours on the process, as the dealer tech would.

    I suggest you start by making sure that both fobs have the silver Toyota emblem (if they do not have a silver emblem, they are not intended for the Smart Entry/Smart Start system) and that the fobs have fresh CR2032 batteries installed. Also, your car logged a low voltage DTC (C1241) which implies the 12V battery needs to either be replaced or at least put on a charger overnight, 4A current setting if the battery is less than four years old.
     
    #3 Patrick Wong, Sep 16, 2015
    Last edited: Sep 16, 2015
  4. darkgiant

    darkgiant Member

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    To clarify, the fobs are registered to the car as Techstream showed two fobs were already programmed to the car, I tried both a set of new batteries but that did not do the trick. From some more research it looks like it is more of the ECU/Computer issue, but my problem is I don't know how much it would cost to replace and how to do it, but it sounds like it is all behind the glove box.

    As for the low voltage, I ran a diagnostic test on the car that showed the battery loads, and it was giving me healthy numbers at the time, but this was about a month ago, but if I were to charge it, are there proper instructions on here on how to do so?

    As for the troubleshooting advice, are there resources on here that I can follow? I'd much rather prefer figuring out the problem myself than spending a whopping $500+ at a dealer...
     
  5. valde3

    valde3 Senior Member

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    ChapmanF already answered about resources:

    About voltages I think you’re talking about HV-battery. That code is about 12V battery.
     
  6. jdenenberg

    jdenenberg EE Professor

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    If you need the technical manual, PM me and I will give you a link to a zip archive on my web server.

    JeffD
     
  7. darkgiant

    darkgiant Member

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    The diagnostic test that I ran was the 12V Battery, following these steps:


    Not sure if that is an inaccurate way of measuring so?
     
  8. darkgiant

    darkgiant Member

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    I would indeed appreciate this technical manual! I for some reason can't send a PM here, any other particular way to get it?
     
  9. jdenenberg

    jdenenberg EE Professor

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    I started a PM with you that has the link.

    JeffD
     
  10. darkgiant

    darkgiant Member

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    Got it, thanks!
     
  11. darkgiant

    darkgiant Member

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    Can someone please help shed some light here? I have found the diagnosis for this error code, but in order to diagnose this, I need an Intelligent Tester (with CAN VIM) so it can connect to the DLC3, and from there, clear all DTC's.

    I looked up with Intelligent Tester tool, and boy it is pricey ($350+). Any idea of clearing DTC's is possible with the Techstream software itself? I wouldn't mind putting ~$50-$75 on the tool but $350 is certainly out of my range, since I don't intend to keep it once I figure out this Smarkey issue... Any insight on this topic would be wonderful!
     
  12. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Get Mini VCI.
     
  13. jdenenberg

    jdenenberg EE Professor

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    +1 to Pat and a MiniVci only costs about $25, but you do need a laptop running Windows (easier with an older 32-bit version, but I have it running under Windows 10 - 64 bit) to run the (pirated) Techstream software that comes with it.

    JeffD
     
  14. darkgiant

    darkgiant Member

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    I do already have the Mini VCI cable, and have Techstream Lite installed onto my computer, but it asks for a key (I am assuming the serial key), and when I want to perform major actions such as reprogramming key fobs and what not, it takes me to a login page which looks like a page Toyota Dealers would only have access. Any clarification on that?
     
  15. jdenenberg

    jdenenberg EE Professor

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    There is a file on your cd that came with the MiniVCI which will install that key in an old (XP - 32 bit) version of windows. You can do the patch manually using methods that can be found by a Google search.

    JeffD
     
  16. darkgiant

    darkgiant Member

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    So I had resetted the Immobilizer and inputted the pin code, I still see the B2755 error code, but when I also check to program the Key Fobs, it says there are no fobs programmed to the car (it originally showed that two fobs were programmed the car). Now, I am having issues with programming the two "smart keys", and am looking for help on that as I keep failing as I am following TIS steps that it displays.

    That being said, can this still be an ECU issue? How much does it cost to replace the ECU itself?
     
  17. darkgiant

    darkgiant Member

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    Uh, BUMP? Looking for some help here!
     
  18. ericbecky

    ericbecky Hybrid Battery Hero

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    You say you recently bought the car.
    Did the two keys you have EVER have the ability to unlock the doors?

    The "turn the car on via the slot" is a completely different function than "remotely unlock the doors"

    And one other question, is the little button by the driver's knee labeled "Key" pressed in, or sticking out?
     
  19. darkgiant

    darkgiant Member

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    The two keys never unlocked or locked the cars when I purchased the car, but if you read above, the issue is communication from the Immobilizer (Error B2775). I cannot program the smart key funciton because of this issue, thus I am asking for some help here on the Immobilizer (in particularly to the Certification ECU).

    After following Toyota's manual for this particular error, I am now 80% sure it has something to do with the Certification ECU, but I again do not know how I can access it, I know it is located behind the speedometer, but I wouldn't know exactly how to determine if it is working, or if it just has a bad wire connection and what not, which is what my main question now is.
     
  20. Patrick Wong

    Patrick Wong DIY Enthusiast

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    I suggest you need to subscribe to techinfo.toyota.com to get answers to your Qs.

    Also, I am not sure that it is reasonable to expect the hacked Mini VCI to be able to execute the security functions.