Can P1121 eventually lead to hybrid battery failure?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by jta98z, Apr 30, 2018.

  1. jta98z

    jta98z Junior Member

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    Hey guys. P1121 has been on on my car for the last 2-3 months. I've ensured coolant levels are fine so no issues there.

    Well just this morning, I'm starting to notice some swings in my SOC meter indicative of HV battery failure. I know this because I'm on my second battery (remanned unit installed by local hybrid shop), thankfully still under warranty.

    But I'm beginning to worry they may refuse replacement if they see the CEL. Is this even remotely possible?

    I've read that the coolant control valve being bad can somewhat affect engine warmup time. So have I been theoretically increasing strain on the battery every time the engine is cold by not replacing the valve?

    Dumb question?
     
    #1 jta98z, Apr 30, 2018
  2. fotomoto

    fotomoto Senior Member

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    No, the two issues are unrelated. Your theory is backward; the longer the ICE runs, the less your battery is used (and thus lower fuel economy). In fact, the ICE running more and harder is also one indication of a weak/failing traction battery. A good shop will read and understand the code is unrelated but I wouldn't think they aren't going to repair it till it throws a battery related code. Good luck with your warranty!
     
    #2 fotomoto, Apr 30, 2018
    m.wynn and SFO like this.
  3. jta98z

    jta98z Junior Member

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    Oh I know. But I’ve still got over a year left in warranty so if it’s already starting to act up I’m hoping it’ll just fail within a year lol.
     
    #3 jta98z, Apr 30, 2018
  4. Erik Owens

    Erik Owens Member

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    Dont use that indicator since it is not exact by any means. You would be the fourth person on this forum I have told. You would be the seventh person total. There is an SOC actual scan tool data that you can go off of. Also you would have to drive and regen brake to ensure Voltage Battery and Intensity Battery were tweaking out on graph mode while using a scan tool as well to ensure your battery was being damaged. But its not.
    The Valve is stuck and there is a TSB for it as well. You will still pay for it and not covered any longer but your engine if you keep ignoring is liable to suffer if you dont get that guy fixed. You will probably notice poor fuel economy for now.
     
    #4 Erik Owens, Apr 30, 2018
  5. jta98z

    jta98z Junior Member

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    Well, on the way home the car acted much more normal. No eradic swings and quick drains etc.

    Is it possible something was just off this morning and has now corrected itself?
     
    #5 jta98z, Apr 30, 2018
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