Scangauge: Showing Codes That Start With Letter "U"

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Aaron, Jul 21, 2008.

  1. Aaron

    Aaron Member

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    When I press SCAN my Scangauge II shows that there are no codes and everything is normal. However, after a few minutes in the same screen it starts to show codes that start with the letter "U" and they are constantly changing. U3F91, U3174, U2F72, U2C6F, U2568, U2B6E, U3F90 and so on....what the heck is this?

    I exit that screen and go to scan again and NO CODES FOUND --READY-- everything normal. No check engine light. It's as if the Scangage II is reading something as I am driving along that isn't problem related like the "P" codes.
     
    #1 Aaron, Jul 21, 2008
  2. ceric

    ceric New Member

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    Aaron,
    It looks like unicodes to me.
    Other than that I can't help much. Sorry.
     
    #2 ceric, Jul 21, 2008
  3. Aaron

    Aaron Member

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    What are unicodes? Anything to worry about?
     
    #3 Aaron, Jul 21, 2008
  4. Bob64

    Bob64 Sapphire of the Blue Sky

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    Those codes don't exist in the bentley prius repair manual... I'd assume its a scangauge bug.
     
    #4 Bob64, Jul 21, 2008
  5. Aaron

    Aaron Member

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    Good.
     
    #5 Aaron, Jul 21, 2008
  6. fnc

    fnc Metro owner

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    Hello,
    Uxxxx codes indicate a communication error between electronic control units. The four digits after the refer to the module complaining about the problem and what the complaint is.

    One thing to keep in mind is the CAN protocol on the Prius changed in the later models. Some scan tools, (CAN tools) set faults just by attempting communication on the bus. I have seen thismany times.

    I will post an example once I locate the pics.
     
    #6 fnc, Jul 22, 2008
  7. fnc

    fnc Metro owner

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    Here are some codes I pulled from a 2005 Prius that would not start. It had multiple communication errors.
     

    Attached Files:

    #7 fnc, Jul 22, 2008
  8. nerfer

    nerfer A young senior member

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    What version of the SGII do you have (MORE>MORE>VERSION or something like that)?
    Is the vehicle turned on (not just in Acc mode) when you looking for these codes?
    <edit: reread the post, you are driving> Make sure everything is securely connected and the cable isn't being too compressed by something. I'm not sure if these comm errors are between ECUs in the car or between the ECUs and the SGII, but it's an easy place to start.
     
    #8 nerfer, Jul 22, 2008
  9. Aaron

    Aaron Member

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    Cable being compressed? Really? I do have the cable tightly wedged around the steering column.

    The strange thing is that everything is running perfectly normal with the car. No warning lights or anything. I just find it strange that I can see "U" codes jumping around changing every second. It seems to me that this is more of a SGII issue that does not affect the car.

    It might be interesting to note that I switched some of my x-gauges to PASSIVE rather than active and I had less errors.

    I am running Version 3.15 (not 3.15*). Brand new out of the box.

    I'm not too knowledgeable on the difference between active and passive codes. Can someone explain this too me? Which is better?
     
    #9 Aaron, Jul 22, 2008
  10. Aaron

    Aaron Member

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    I think this is what is happening. But why isn't it affecting my Prius in a bad way? It starts up fine.
     
    #10 Aaron, Jul 22, 2008
  11. fnc

    fnc Metro owner

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    It depends on the exact code. If you set a fault like in the image I attached above you would have all the fault lights set. If you are just setting low priority codes no lights will illuminate and you will not notice.

    Communication faults are common on all makes, they do not always can an issue the consumer notices.
     
    #11 fnc, Jul 22, 2008
  12. Bob64

    Bob64 Sapphire of the Blue Sky

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    Most if not all the listed U codes in the repair manual starts with U0, not U2 or U3 like aaron is seeing...
     
    #12 Bob64, Jul 23, 2008
  13. fnc

    fnc Metro owner

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    We are also relying a generic interpretation of manufacturer specific communication codes. These types of codes are not standard or regulated to be standard. They vary by make and by year. I would guess scangauge is displaying them incorrectly.
     
    #13 fnc, Jul 23, 2008
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