Corroded terminals, bus bars, and voltage sensor wire harness

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Matthew Holloway, Nov 3, 2022.

  1. Matthew Holloway

    Matthew Holloway New Member

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    Hello all,
    I have a 2012 Prius with 77,000 miles on it. I live in Hawaii, so very salty and humid.
    I had the triangle of doom and "check hybrid system" error message. I cleaned the battery cooling fan and everything seemd fiine for a few weeks.
    I recently got the triangle and message again. I have a cheap OBD reader, and no codes came up.
    I opened the HV battery and there was a ton of corrosion on the terminals, bus bars, and voltage sensor wiring harness.
    I tested each battery block and all voltages read 7.5. My 12v battery is reading 12.1 after sitting a coupe days.

    I have only been able to find used voltage sensor harness on ebay, and only nickel plated bus bars.
    Does anyone know where to get OEM replacements?

    Any other ideas or suggestions are welcome.
    IMG_0237.jpg IMG_0241.jpg IMG_0240.jpg IMG_0239.jpg IMG_0238.jpg IMG_0237.jpg IMG_0241.jpg IMG_0240.jpg IMG_0239.jpg IMG_0238.jpg IMG_0237.jpg IMG_0241.jpg IMG_0240.jpg IMG_0240.jpg IMG_0239.jpg IMG_0238.jpg
     
  2. Tombukt2

    Tombukt2 Senior Member

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    All those wires and connectors the orange ones can be cleaned up with CRC electrical cleaner or battery terminal cleaner it turns yellow or something when it mixes with battery acids and the like it'll clean those up real nice The nickel plated bus bars are okay they do pretty well you should get the nuts that go with them a relatively cheap like $23 a set or something they do okay if your daughter has a rock tumbler you can put the copper ones in the rock tumbler with some fine rock or media and that will clean those up nicely but I think I'd still prefer the nickel plate a jobbies and they look real good too but you need to make sure you get those orange wires with the silver plated holes drilled in them that connect to the mains and all that cleaned up good Make sure their connections are good and not frayed etc . And wire it all back up see what ya get . But do it quickly few days etc
     
  3. Tombukt2

    Tombukt2 Senior Member

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    The longer it sits the worse things get
     
  4. PriusCamper

    PriusCamper Senior Member

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    Looks entirely normal... The battery chemistry technology Toyota uses is 40 years old and 40 years ago corrosion with car batteries was an issue. Primary point of failure is where your photo's wiring plugs into the battery ECU. Open up the ECU and clean out the corrosion growing on that plug on the inside to avoid P3000 related error code shut downs.
     
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  5. Paul E. Highway

    Paul E. Highway Active Member

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    Agree with cleaning up the wiring to the ECU. Also cleaning up all the connections (bus bars and nuts) can only help. How old is your 12v battery? And keep in mind your traction battery is 10 years old, you might be on borrowed timeā€¦
     
  6. Matthew Holloway

    Matthew Holloway New Member

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    I cleaned up all the bus bars, nuts, wires and connections. Doesn't seem to be throwing a code, but MPG is still pretty low. Around 36mpg.
    My OBD reader should arrive today and I'll check the battery with the dr. prius app.
     
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  7. Tombukt2

    Tombukt2 Senior Member

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    Yeah it'll take a while for your mileage to go up course without knowing what the battery is trying to do but if you took it out on a decent run somewhere where you can be out in the county not necessarily on the interstate your car should tell you if that battery is charging pretty well that's bouncing around from empty to full and acting silly then not so much you don't have the Ah you should
     
  8. Mendel Leisk

    Mendel Leisk Patron saint of newly poured sidewalks

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    Post the Dr Prius result. The bar graph showing blocks, with volts and ohms.
     
  9. Matthew Holloway

    Matthew Holloway New Member

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    Here are the Dr. Prius results.
     

    Attached Files:

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  10. PriusCamper

    PriusCamper Senior Member

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    How old do you think those error codes are? How long do they take to come back after you clear them?
     
  11. Matthew Holloway

    Matthew Holloway New Member

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    Hard to say, I just got my Dr. Prius compatable OBD reader.
    I will clear codes and see
     
  12. PriusCamper

    PriusCamper Senior Member

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    Yeah... The first time you check out a car's error codes there's usually ones in there that are glitches from long ago that are no longer a problem. Let us know what comes back? Also learn about how to restore battery capacity: FAQ (Frequently Asked Questions) | Hybrid Automotive You can build your own gear to do this for $100: Build Hybrid Battery Maintenance Gear For Under $100 | PriusChat
     
  13. Matthew Holloway

    Matthew Holloway New Member

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  14. PriusCamper

    PriusCamper Senior Member

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    It's really simple and as usual PriusChat has too many cooks in the kitchen confusing everything...

    All you need is a high voltage trickle charge that feeds electricity to a 220v DC system at near 1/2 amp... Then use light bulbs to deep cycle/discharge to restore lost capacity 3 times after each full charge & balance. Any questions you have, just post them here and I'll walk you through it!
     
  15. Matthew Holloway

    Matthew Holloway New Member

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    Haha yes, Seems like it's gotten a little confusing on that thread.

    I read the whole build by pmarkH and yes, it seems doable. But still a little sketchy.
    Guess I would like to see a build thread that's a little more concise and exactly what I need for my gen 3.
    Def. more affordable than the other option, which is to get the prolong charger and discharger.
     
    #15 Matthew Holloway, Nov 9, 2022
    Last edited: Nov 9, 2022
  16. PriusCamper

    PriusCamper Senior Member

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    Yeah... High Voltage is no joke and proceeding with caution is the correct approach. However, once you get one built, you'll look back on it and realize it was no big deal and lack of experience in building one was the only real challenge.
     
  17. Matthew Holloway

    Matthew Holloway New Member

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    Have you completed one? I'm about to pull the trigger and get the parts, but honestly it's still a little confusing. I'm not really seeing a finalized complete build or schematic
     
  18. CatNinja

    CatNinja New Member

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    Hi @Matthew Holloway, I just started down this path myself, and should be completely done by Sunday. See What type of connector does a Prolong Charger/Discharger use? | PriusChat

    Do you live in Oahu? You are welcome to stop by and see my completed build. You are also welcome to borrow my charger/discharger to see if it works for you, before investing in building one yourself, or buying a pre-built prolong setup. All you have to do is build your own harness, less than $20 in parts.
    IMG_5281.JPG
     
  19. Matthew Holloway

    Matthew Holloway New Member

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    Oh man, that would seriously be awesome. I'm in Haleiwa.
     
  20. CatNinja

    CatNinja New Member

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    I'm in Manoa, right behind Punahou School. Let me finish up charging up my Prius this weekend, then, hopefully, I won't be needing my setup for another 6 months, and you can borrow it after. You'll probably need a week anyway to source your the parts for the harness, since shipping to Hawaii takes forever. Do you need help with it? It's pretty straightforward, just a cable with a female Ideal Disconnect (from Homedepot) on one end, and ring terminals on the other. I also highly suggest an inline fuse holder with a 2A DC fuse as close as possible to the positive battery terminal. The hardest part was actually getting the lengths correct so it fits neatly.

    Just watch my progress on the other thread to see when I'm done, and message me when you have finished building the harness.
     
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