Check Engine Question

Discussion in 'Gen 2 Prius Main Forum' started by jcoasternut, Dec 5, 2021.

  1. jcoasternut

    jcoasternut Junior Member

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    My check engine light came on in 2008 prius with approx 150000 miles. Scanner code is U0100 Lost communication with ECM/PCM.
    It is starting and running fine. I stopped driving as soon as it came on, was only a few blocks from home.
    My question is I am not planning on driving it except possibly to the Toyota dealer approx 5 miles away. Do you think it is safe for me to drive to the dealer or should I have it towed.
    Thanks !
     
  2. Tombukt2

    Tombukt2 Senior Member

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    Why would you stop driving that do you drive so much that you're going to be so far away from everything that you think you'll be trapped or the light makes you nervous and that ends the trip naw. I have every amber light in my car on they've been on now for over a year The car drives perfect The brakes work fine You think I'm going to stop driving getting near 50 miles to the gallon because some amber light came on That's funny but yeah drive it to the Toyota dealer I guess and let them scan it with tech stream That's a code I don't recognize but sound like it's intermittent I would like to know what the tech stream codes are which is what the dealer will use to scan with or if you live near somebody here on the list they may have that tech stream most people do now and you could do it for near nothing I don't know why people like to go to the dealer and pay $175 to have their car scanned or something similar when they can do it in their driveway with pretty much the same tooling and own it for about 80 bucks and use it whenever they want I guess that's just out of range of a lot of folks or it's cheaper in their minds to pay the $100 and whatever dollars and have someone else do it

    SM-A715F ?
     
  3. Tombukt2

    Tombukt2 Senior Member

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    You don't have the red triangle That's when you need to use more precedent to find the problem and narrow it down because that will stop a show and that's why people almost immediately tell you I've got the red triangle of death because they know next is problems just the amber lights coming on you know the check engine light ABS-VSC and all that check those systems see what you got if pedals and everything are working I stay in mind and keep driving it till that pedal doesn't work right etc I'm not getting out

    SM-A715F ?
     
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  4. jcoasternut

    jcoasternut Junior Member

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    The only light on is the amber check engine picture. It on steady and not flashing. I am retired and just want to make the car last until I stop driving in a few years so wanting to make sure not damaging car in any way. Bought it new in February 2008 and it has always been well maintained.
     
  5. Tombukt2

    Tombukt2 Senior Member

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    Yep mine's an original '09 I'm the second owner it's been well maintained it's gold with that ugly tan interior that turns black everywhere you set your skin on it but other than that it always gets 47 plus miles to the gallon tires last a long time it's the lowest maintenance car I've ever owned and I've always had Toyotas right at 300,000 now and expect to go to five or six basically even with all the amber lights on it should go no problem. You should ask the guys on here if anyone lives near you I'm in North Carolina with tech stream and all that kind of nonsense anytime anybody's in North Carolina they're welcome to come by here and we can play with their car all they want got plenty of tools and toys no problem but I don't know where everybody is on this list but they're all over the place I don't think you're damaging the car in any sort of way so far and as a 2008 or 9 owner as old as that car is there are very few people that even know how to work on it anymore it's getting that wild so you need to find somebody that owns a few works on them when they're goofing off etc somebody that cares a job shop doesn't care about your car generally speaking they care about working on 300 cars a week and making $250,000 or similar it doesn't matter to them who's and what You may want to find a mechanic that might care about those things You and your car most places you know seriously don't look at how the internet is taken over businesses and businesses have actually in many cases gotten not better just beware of that it's not just you and I seeing that

    SM-A715F ?
     
  6. jcoasternut

    jcoasternut Junior Member

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  7. Tombukt2

    Tombukt2 Senior Member

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    My brother's out your way I hope you find somebody that'll take good care of you and keep your car to well I don't know how far you can go at this point but these Gen 2's can go long . Usually it's not the car most of the time it's the owner they just want a new car they made some more money etc they're entitled.

    SM-A715F ?
     
  8. davecook89t

    davecook89t Senior Member

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    I will second the opinion that the car will not be damaged by driving short distances with only the Check Engine light showing. A more serious problem would always light up the Red Triangle.
     
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  9. ChapmanF

    ChapmanF Senior Member

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    What did you use to read the codes? Does it indicate which ECU reported each code?

    Background: when you use something like Techstream, it shows you all of the trouble codes from the car, grouped by which ECU they came from. But some other scanners only show you a bunch of codes, and not where they came from.

    That especially matters with communication codes (the kind that start with a U) because even knowing that U0100 means "lost communication with ECM", you can still want to know which other ECU in the car can't communicate with the ECM, and knowing that you can make a better-informed judgment about how dependable the car is going to be or how urgently you want to address the problem.
     
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  10. jcoasternut

    jcoasternut Junior Member

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    Don't know much about the scanner. IMG_1209.jpg
     
  11. jcoasternut

    jcoasternut Junior Member

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    Don't know if the above picture helps any. First time using a code reader bought at Walmart for around $20.
     
  12. PriusCamper

    PriusCamper Senior Member

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    Drives me crazy when people bring their car to me with too many dash lights on (specially low tire pressure warning light). Those dash lights are designed to give you advanced warning of specific problems so you can avoid destroying your vehicle or getting yourself killed in an accident.

    You need to get one of these devices: Hybrid battery diagnostic and repair tool for Toyota and Lexus and keep it in your glove box and use Dr Prius app to grab error codes and clear warning lights soon as they show up if you want to ensure your car keeps running well... Replacing your Prius given the current status of the used car market will not go well for you if you have to do that. Used Gen 2 Prius that were selling for $4K are now selling for double that. It's nuts right now! Protect your vehicle!
     
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  13. Tombukt2

    Tombukt2 Senior Member

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    I have text her in here I just replaced the battery the reason all my ambers are on has to do with my ABS system low pressure and the right rear I guess it knows that by reading the ABS pump up front the brake function fine I don't think they're anti-lock at the present time if I step on the brakes right smartly I can smoke all four wheel wells looks very cool but it's not good to be doing that my tire pressure monitor lights on because probably more than one TPMS sensor is probably dead I'll get it around to that on the next tire change

    SM-A715F ?
     
  14. Tombukt2

    Tombukt2 Senior Member

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    Tech stream

    SM-A715F ?
     
  15. Tombukt2

    Tombukt2 Senior Member

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    I bought a used tech stream from a Toyota dealer that went out of business and before he handed me the Panasonic laptop he had downloaded all the 2021 updates for all the computers all the key fobs every stinking thing available it's all on the machine because I don't have a login for Toyota so I can't run tech stream live and get instant updates as they come out now my buddy at the parts department has a login I might get his one of these days but as it stands now I don't use a login I just use text stream as it's on the computer The cable they supplied me looks like the one in the picture that comes with this laptop with tech stream on it. It all seems to work reasonably well All my lights are on because like I said my ABS system is not ABS at the moment and to fix it the car will be down for a minute and it's all working great so I just leave it if I turn the lights off the minute I step on the pedal brake pedal they come right back on if I don't touch the pedal they will not come on

    SM-A715F ?
     
  16. edthefox5

    edthefox5 Senior Member

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    Steady check engine light is usually emissions related like a P0420.
     
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  17. Tombukt2

    Tombukt2 Senior Member

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    Yep cat threshold it's been on since the old converter was in place I changed it out along w den stream 02 still mil lite I don't know what threshold I'm below but whatever it's all good My 02 Corolla was the same way with the had a computer made by Delco I think and the O2 sensor upstream and downstream were way too tight they had a update for the computer that widened that parameter apparently would keep the light off I never got it done I just unplugged it

    SM-A715F ?
     
  18. PriusCamper

    PriusCamper Senior Member

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    Lol, it's good you're curious about what your warning lights mean... Do more of that! And yes, I could probably drive with a bath towel over my windshield and my head out the window just fine for a long time. But...
     
  19. mr_guy_mann

    mr_guy_mann Senior Member

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    Ummm, ANY check engine light activation is something "emissions related" - as required by law. It might be major, it might be minor, but it's all about emissions.

    Posted via the PriusChat mobile app.
     
  20. PriusCamper

    PriusCamper Senior Member

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    This would be something that @Elektroingenieur could elaborate on the history of... It'd be interesting to know more about how they seperate emissions related error codes from other error codes?
     
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