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Multiple Diagnostic codes P0505 P1121 P0205 P0511

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by alembic42, May 8, 2019.

  1. alembic42

    alembic42 Junior Member

    Joined:
    May 8, 2019
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    Location:
    Pittsburgh
    Vehicle:
    2005 Prius
    Model:
    LE
    I recently purchased a 2005 Prius, 160K miles. This is my first hybrid car. Also my first experience with a Check Engine light on any car.

    It runs basically well, the ICE is perhaps a little loud and choppy, but given its age i didn't think much of this. Other than the lights and codes i have no particular indication of any problems.

    On the way home from buying this car (!) i got a check engine light. I kept driving and after ~40 miles including 20 miles on the freeway, I also got the High Voltage System warning light. Not happy about this but I'll spare you. I didn't drive it much for a couple days, and I started getting my act together, and used Car Scanner on my iPhone along with a Bluetooth 4.0 LE adapter to retrieve the following codes:
    P0505 P1121 P0205 P0511

    This car has I contacted the girl who sold it to me, as nicely as possible, and she told me (now, not earlier) that this has been happening for a long time. Well, it sounds like the check engine light has been coming and going for a long time, and the high voltage light more recently. Toyota dealership couldn't figure out the check engine light but they replaced a lot of stuff in the process, she says - she reported having had the O2 sensor replaced as well as all 4 water pumps. She blamed it on a bunch of BS about the prius being too sensitive. Some crap that a "mechanic" who couldn't figure it out probably told her (whether or not at a dealership).

    I read that a combination of these lights (CEL+HVS lights on the dash) can be caused by a failing Inverter Water Pump. But this was supposedly replaced after the problem started. Reading more, I stumbled upon another proposed cause, a failing Water Valve Assembly Valve With Bracket. Sounds reasonable.. I can do this, hopefully myself, but I don't want to throw money away replacing random stuff here.

    The other codes seem to point vaguely to an "injector circuit malfunction" on Cylinder 5. Pretty sure this car doesn't have a cylinder 5. I do see some indication about cleaning the throttle body. This sounds like a reasonable thing to do, not too hard or expensive, i guess i can go ahead and do that this weekend.

    Can anyone give me some insight on this?

    Thanks so much for your helpful replies.
     
  2. SFO

    SFO Senior Member

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    Vehicle:
    2007 Prius
    Model:
    N/A
    Welcome to PriusChat!!

    Worried about the OBD2 scanned codes you posted, as the gen2 has 4 cylinders. Have you tried using another scanner to see if the retrieved codes vary at all? (auto parts stores sometimes scan for free, a friendly mechanic, free scan advertisements or offers)

    Also try using a different iPhone app, as your mentioned app may not be hybrid compatible, or even supported at this date. Not sure which app for the iPhone is currently in vogue, see if something in here fits : OBDII iPhone App | PriusChat

    Maybe this iPhone app could be usable, though it may need configuring : Engine Link for iPhone | PriusChat

    Pretty sure many iPhone users on PriusChat use this app, and the author is a contributor here : Hybrid battery diagnostic and repair tool for Toyota and Lexus

    For detailed dealer level diagnostics, most on here use Techstream and an OBD2 cable connected to a laptop or similar.
     
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  3. Skibob

    Skibob Senior Member

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    Location:
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    Vehicle:
    2006 Prius
    Model:
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    I second a mini VCI and Techstream
     
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  4. exstudent

    exstudent Senior Member

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    Location:
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    Vehicle:
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    1) The previous owner likely reset all the lights before selling to the next victim (you). Best to pay for a through examination of future vehicles you don't know about.

    2) Techstream is the OFFICIAL diagnostic and maintenance software made for Toyota/Lexus, and used at Toyota/Lexus dealerships. Bluetooth OBD2 readers and all the various apps for smartphones/tablets are junk: LIMITED code reading ability (can't read ALL codes) and can NOT do any maintenance (bleed brakes, engine compression check, activate CHRS pump, etc). Why waste money on a toy that limits what you can read and can't do maintenance?

    "But I don't DIY." Getting the codes read at a Toyota dealership will set you back $100+. The cost of the hacked Techstream from Amazon will pay for itself.

    Get mini VCI w/ Techstream from Amazon ($18+). Doesn't matter who you buy from, as the cables likely come from the same one or two suppliers from panda land. May have to return/buy a few, as some cables have problems (bent pin-easy DIY fix, to dead cable). Installation easiest on a Windows 32bit OS (XP, Vista, 7). Ask friends/family if they know someone in IT, as this person will likely have obsolete laptops laying around, and might be able to donate for free. B/C the software is hacked, recommended to install on a spare laptop; do not use this laptop for sensitive information (log in & passwords: email, bill payments, etc). This laptop is now your Toyota/Lexus diagnostic laptop. Mac install possible, you just need to search online.

    Should you stop driving a Toyota/Lexus, you can easily sell your Techstream laptop set-up here.
    Private Sales | PriusChat

    3) DTC P1121 is probably a valid code. The 3-way coolant control valve is a part that will die over time. Nothing new, exciting, or special about it; any part in use will fail at some point in time. If the valve is stuck in the wrong position, it will cause longer engine warm-up times, lack of cabin heat, and unable to get vehicle registration due to the CEL being illuminated.
     
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  5. alembic42

    alembic42 Junior Member

    Joined:
    May 8, 2019
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    Location:
    Pittsburgh
    Vehicle:
    2005 Prius
    Model:
    LE
    Ok. I am the OP. I fixed this.

    All the CEL codes were fixed by:
    Replaced Coolant control sensor thing mentioned above,
    Replaced air filter
    Cleaned MAF and air intake

    The red triangle was because of the headlight adjustment sensor in the back, had to replace that plus the wires leading into it wow. Additionally the HID headlights were all F’d - I’ve heard this costs $$$ or $$$$ but I fixed that for $55 by switching to LED and cleaning the lenses. Took all day just to do this tho!
     
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  6. SFO

    SFO Senior Member

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    Could you please link to the purchased LED product so that others can potentially benefit from such.

    Or start another thread if you like (y)
     
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  7. alembic42

    alembic42 Junior Member

    Joined:
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    Vehicle:
    2005 Prius
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    LE


     
  8. tri4all

    tri4all Member

    Joined:
    Oct 20, 2019
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    Location:
    Pacific Northwest
    Vehicle:
    2008 Prius
    Model:
    Touring
    hi Alem, can you give us a status of how those lights are working out after a few months? amazon says that they are not compatible with my 08 prius.
     
  9. alembic42

    alembic42 Junior Member

    Joined:
    May 8, 2019
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    Location:
    Pittsburgh
    Vehicle:
    2005 Prius
    Model:
    LE
    Yep. The lights are fine. The deal is that if you have halogen lights then you can buy a better brand, opt7, I think the type is H4. Anyway my car came with HID headlights and these are an adequate not awesome replacement for that. I removed the ballasts and soldered the new connectors onto the wires that used to go to the ballasts. Not too complicated but it took me all day one day in the summer.


    iPhone ?
     
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