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Skid Control ECU Issue (Resolved)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Ang3l0, Jan 5, 2016.

  1. Ang3l0

    Ang3l0 New Member

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    A local guy replaces my battery and offered me a warranty. The red triangle, yellow exclamation, vsc and break light came on again and the charging was acting strange so I asked him to come take a look. We used his computer to pull this report (picture below) he said he would replace the Skid control ECU for less than 200 and was confident it was not the battery. He seems like an honest and nice guy but I don't quite understand how to read the codes. Any opinion would be greatly appreciated. Thank you!
     

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  2. bisco

    bisco cookie crumbler

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    welcome! how about he replaces the ecu, and you pay him after it proves to be the problem. or is he just going to keep replacing parts until he pins the tail on the donkey?
     
  3. Ang3l0

    Ang3l0 New Member

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    thank you for the warm welcome! I won't be paying him until after the work is complete. So it may actually work out that way. If he has to unplug the battery to install the ECU the codes will go away so it will be hard for me to tell immediately if that was the solution. I guess if the errors come back a day or so later I will know he assumed wrong. I've had Honda accords and civics my whole life lol diagnosing hybrids seems so complicated to me. Originally I thought it was an issue with the battery because it was going from full charge to medium charge to low charge and back up again within a 10 miles drive. But I just moved back to a state that actually has winter so I don't know if that's normal. I thought it was odd when the battery reached full since I rarely see it that high.
     
  4. bisco

    bisco cookie crumbler

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    the battery does go to full green sometimes, and two purple bars. but most of the time, should hover around 6 blue bars.
     
  5. ChapmanF

    ChapmanF Senior Member

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    Well, the way you read that screenshot is that there are a lot of codes being reported from several different computers in the car. The hybrid control, power steering (EMPS), air conditioner, cruise (probably not a separate computer, I believe it's integrated into the hybrid ECU), and yes, the ABS/VSC/TRAC (your "skid control" ECU) is also reporting several codes.

    Maybe his way of interpreting trouble codes is to count them and say "well, the ABS/VSC/TRAC has the most, that means I should replace that computer"?

    The way I would interpret them would be to look them up on a Toyota 2005 Prius repair manual. It doesn't just give a list of one-liner descriptions, it tells in detail what conditions cause each of those codes to come up. Sometimes it will say to get further information about one of the codes. All the codes you see listed there with a little white cloud-shaped icon have further information to use. For some of the codes the manual may also say to run certain tests, or take certain measurements. I would do that.

    Because there are several codes there and they are showing up in several separate computers, the set of possible causes is going to narrow pretty quickly as you (or the mechanic) goes through the process of finding the possible causes that they may have in common. It looks like a pretty interesting situation. Wiring or connector damage to the network that interconnects those computers would be one possibility--but only one, and I'm way over here where I can't do any of the work of testing or confirming it for you, so I'm not saying it's the answer. I'm sure you will find the answer, though, or your mechanic will, if you just persevere in looking up the codes you've been given and following the steps to diagnose them.

    -Chap
     
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  6. Ang3l0

    Ang3l0 New Member

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    Thank you so much Chap! I found a PDF Repair manual and the codes that I see associated to the brake system refer to exactly what he said. the skid control ECU. I am having trouble finding the Hybrid control codes but to be honest this PDF manual came as single pages that are confusingly labeled. Haha this couldn't have happened at a worse time, the wife is due to have our first in 7 days. but that's how it goes with cars eh? I'm going to keep digging through this manual, he's coming back to replace it in 2 days so I'm going to use that time to do my research and confirm his theory.
     
  7. ChapmanF

    ChapmanF Senior Member

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    If the time and aggravation are worth something more than $15 to you, you can always go straight to techinfo.toyota.com and know what you're getting. You're not looking for one-liner fortune-cookie descriptions of what your codes "mean". You are looking for the sections, usually anywhere from a couple pages to ten or twenty, that actually tell you what conditions the computer is responding to when it gives you those codes, and what troubleshooting steps you can follow to get from that information to an understanding of what the problem is with your car. If you haven't found those sections yet, you kind of haven't started yet.

    -Chap
     
  8. Ang3l0

    Ang3l0 New Member

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    He came by today and he is working on it currently. we will see what happens

    Well, he was able to resolve most of the codes. he spent a good 5 hours working on my car. Funny, he actually saw my post on here as well. He was having trouble getting the new ECU calibrated and that is what caused the 2 remaining codes to appear. All said and done he replaced the battery because he did not like the codes that came back from the battery and he replaced the ECU. I should mention this was the 4th car he had worked on with the same codes appearing so if anyone else on this forum finds these codes it may be a skid control ECU. all said and done I am very happy with the results and I have learned a lot about my car along the way. The user's name is Straw Brad and he's a great guy if you ever happen to get advice from him. He actually ended up charging less than I anticipated. Talk about Minnesota Nice!
     
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  9. Texas Hybrid Batteries

    Texas Hybrid Batteries Senior Member

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    Brad has lots of knowledge to share on all things Prius and hybrid battery related and at this point I'd bet he has more experience replacing skid control ECU's than Toyota.:) I'm curious what type of calibration has to be done when replacing the skid control. I swapped skid modules on a car a few weeks ago because the car would't pass a linear solenoid valve calibration. When the ECU didn't fix the issue we replaced the brake actuator (ABS Unit) and that ended up being the problem. This was all done after we tried a full flush and bleed on the brake system.

    There is a pairing procedure that must be done when replacing the Hybrid Control module, is there anything like that for the Skid control?

    Also, I know there has been discussion about part number interchangeability on the skid control ECU. I swapped the (47100) module from my 2006 with a (47080) module in a customers 2005 and they both worked great. Didn't even worry about switching them back. My guess is that all of the modules (I think there are 4 different P/N's available) are interchangeable across any of our Gen 2 cars.

    Matt
     
    #9 Texas Hybrid Batteries, Jan 9, 2016
    Last edited: Jan 9, 2016
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  10. m.wynn

    m.wynn Senior Member

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    Really fun to read through this thread and then see it was strawbrad helping you out. As you now well know, you've found a gem when it comes to Prius electrical wizardy.
     
    #10 m.wynn, Jan 9, 2016
    Last edited: Jan 10, 2016
  11. bisco

    bisco cookie crumbler

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    congrats. wish you had told us his name in the beginning. straw brad is very, very good. all the best!(y)
     
  12. OldBuddha

    OldBuddha Junior Member

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    my local Toyota dealer wants $2,000.00 to replace my Skid Control ECU. Is this reasonable?
    There is a long story that goes with it.
     
  13. Teresa Y Kirkpatrick

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    Mine wants $3600 - part $2800 , labor $800. He told me he would trade it in for something cheaper to repair. I love my car, though, and it still runs well, athough the dash lights go in and out.
     
  14. ChapmanF

    ChapmanF Senior Member

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