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ABS VSC and (!) lights and brake warning alarm

Discussion in 'Gen 2 Prius Technical Discussion' started by Clancy Bond, May 19, 2024.

  1. Clancy Bond

    Clancy Bond New Member

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    My 2008 Toyota Prius odometer 188,000 through these warning lights ABS VSC (!) with the red triangle along with my power steering and braking losing power and then my battery drained on the same evening.

    I had the battery charged and load tested it was fine but it was time for a new battery so I went ahead and purchased a new yellow top. Every time I put a newly charged battery on all signs of any problem go away until the third or so time I park the car and start it again. Then they’ll all pop up again with loss of power steering and the car would keep going into neutral the whole time with this high pitched brake alarm going off. Every time the battery drains as well.

    I took the blinker codes but I’m not fully sure what they mean here they are (!) 43 & 41 ABS 42 VSC 45

    Has sounded like a bad DCDC converter symptoms but I haven’t been able to find out how to test that.

    the only engine codes that were popping up were related to the electrical coolant pump which I replaced just in case it was causing any problems but it has not solved the problem.
     
  2. Clancy Bond

    Clancy Bond New Member

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    Also I suspected the abs actuator but it still turns on when the battery is charged and it’s not running every few seconds like I suspect bad one would.
     
  3. Tombukt2

    Tombukt2 Senior Member

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    No but that constant beep that you have is related to what I have noticed to be some kind of pressure in the ABS accumulator or system that beep is on and it doesn't go away if it does while you're driving down the road the system is reached pressure I drove a car like this for almost a year and a half I can tell you all about it as far as that goes until you get that beep and that pressure cleared up in the accumulator or the ABS brake system that beep is going to stay that! ABS and VSC lights in orange are going to stay just because you don't hear the pump running all the time doesn't mean there's not an internal leak in the system maybe the pump is getting wore out and it doesn't run much anymore It gets hot and stops even worse Do you notice your brakes are very poor when the beep is on I'm guessing you're not driving the car?
     
  4. ChapmanF

    ChapmanF Senior Member

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    If you looked here to learn how to take the blink codes: Blink (a/k/a Flash) Codes – How to. | PriusChat

    ... it also told you what ABS 42 and VSC 45 mean (they both just mean "look at the ECB codes", and also what ECB 41 means: "It means a problem with the voltage arriving at the brake system's electrical connections. The problem can be anywhere along the wiring path bringing power there, but it wouldn't be crazy to start by checking the 12 volt battery. If no glaring problem there, then the repair manual has the rest of the troubleshooting steps."

    ECB 43 is trouble code C1377, pertaining to the backup electrical power supply for the brakes. It's the smaller box in the back of the car next to the 12 volt battery. If you can get access to a scan tool that shows INF codes, there are eight possible INF codes for C1377, to tell you more about the issue.

    A Prius brake actuator is a complex machine with a bunch of valves and sensors and a lot of ways to fail. Running every few seconds is one of them. I often see posts like "I don't think I have an actuator problem, because I don't have the exact same actuator problem I read about somewhere else", but that doesn't really follow.

    On the other hand, the codes you have don't point to an actuator problem, so it's fair to spend more time looking where they do point.
     
    Brian1954 likes this.
  5. Clancy Bond

    Clancy Bond New Member

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    No I am not driving except for test drives, like I said the alarm doesn’t sound when a fresh battery is on but after a 2 or 3 power cycles the battery is weakened and all the symptoms come back alarm, lights, and reduced power steering and braking. Once the battery is weakened the car goes into limp mode where I can’t drive it but a few feet.
     
  6. Clancy Bond

    Clancy Bond New Member

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    I’ll see about getting my hands on a scan tool that can read inf codes although that might be a bit as I’m low on funds for this car right now.

    How would I get my hands on a repair manual to look into ECB 41

    Also I’m a little confused as to how a fully charged battery seems to be able to solve the issues but is quickly drained. Again led me to believe something was up with the DC/DC converter but I don’t know how to test that or if that’s even a reasonable assumption with those DTC codes.
     
  7. ChapmanF

    ChapmanF Senior Member

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  8. Brian1954

    Brian1954 Active Member

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    A good scan tool for the Prius is an Autel AP200, $55 to $60 at Amazon. Read this thread: https://priuschat.com/index.php?posts/3290690
     
  9. dolj

    dolj Senior Member

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    ECB 41 is the same as the DTC C1241 and the diagnostic tree for that code has been posted many times in many posts.

    It is reasonable to think there might be a problem with the DC/DC converter part of the Inverter but there are other things. There also are four sub-codes associated with the DTC C1241 – 81, 82, 83, and 84 – which can help focus the diagnostic effort. The six areas highlighted in the RM are:
    • ABS NO. 1 relay
    • ABS NO. 2 relay
    • Harness and connector - Skid control power supply circuit
    • Brake control power supply assembly
    • Hybrid control system
    Following the inspection procedure for the code will help narrow down your efforts.
     
  10. Clancy Bond

    Clancy Bond New Member

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    My Autel scan tool is finally in. I’m not quite sure how to pull inf codes yet but I’m researching it today.
     
  11. mr_guy_mann

    mr_guy_mann Senior Member

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    Once you have the scantool set up through the app and connect to the car, go into the system you want to check. Then look at freezeframe data - one of the lines of data will be the detail (INF) code.
    Screenshot_20230602-090942.jpeg

    Posted via the PriusChat mobile app.
     
  12. Clancy Bond

    Clancy Bond New Member

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    On the dtc C1241 the only detailed freeze DTC I got was “512” not sure what this means yet or if I did the scan wrong on the app but let me know if I’m missing something
     

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  13. Clancy Bond

    Clancy Bond New Member

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    Tried to see if there was anything that I was missing on the app for another 30 min but the only freeze frame data I could pull was for code C1241 and the only “detailed freeze DTC” was that 512 I can’t find that anyway in the repair manual for code C1241. If I’m missing something please let me know!!
     
  14. ChapmanF

    ChapmanF Senior Member

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  15. Clancy Bond

    Clancy Bond New Member

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    I have the car at a dealership to have a diagnostics done on it I’ll post the results in this thread in the coming days.
     
  16. Clancy Bond

    Clancy Bond New Member

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    Dealership was going to charge me upwards 800$ to do the full diagnostics, I don’t hold that kind of value for the car so I sold it for 600$

    I never found out what was going on but I really appreciate your quick reply’s and in depth help.

    thank you.