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Isolating Prius Start Issues

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by DKM, Jan 19, 2020.

  1. DKM

    DKM Junior Member

    Joined:
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    Location:
    Canada, Toronto
    Vehicle:
    2004 Prius
    Model:
    N/A
    Hi All!

    I've had issues with my Gen2 Prius failing to start a couple of times, and I was hoping to clarify what the issue is.

    Context:
    On two different occasions, my Prius has failed to start. On both occasions I believe the issue started, because I had the heating/defrost turned on for a few minutes but then turned off the car (was waiting to pick someone up in the middle of the winter). Upon restart, the car failed to start.

    I suspect it is a 12V battery issue. I checked the 12V battery via diagnostic mode, here are the results;
    Pressed power button, foot off brake (engine off): 11.7V
    Pressed power button again while car is on, foot off brake (engine off): 11.3V
    Pressed power button on, foot on brake (engine on): 13.9V

    Other symptoms:
    • Error Message: "There is a problem with the transmission "p" lock mechanism. Park your car on a flat surface and fully apply the parking break."
    • Park Button was flashing green
    • All other displays (dash) went dark, other lights (break/interior lights) were very dim
    The 12V battery was last replaced in 2011, so it has been a while. However, by the same coin I don't drive much, probably a few KM a day just to get to the grocery store. No long highway trips or anything longer than 10-15 min drive most days. Perhaps I don't drive enough to charge the battery?

    Troubleshooting
    1.) I'd like to be sure the battery is the problem before moving forward without purchasing a replacement.

    Could it be that it simply has not been charged long enough because I don't drive all that often or for that long? How do I charge the 12V battery? Is that a viable solution long-term?

    2.) Assuming the 12V battery is the problem, I am looking for replacements. Any recommendations?

    Currently, I have an Toyota OEM battery, but I've heard tell of other batteries (i.e. Optima Yellow Top). Not sure about the intricacies of these batteries (i.e. deep cell, wet cell, AGM), so any context on that is appreciated! I think AGM is the best bet, but the original OEM battery is expensive.

    Thanks in advance for your help everyone!
     
    #1 DKM, Jan 19, 2020
  2. dig4dirt

    dig4dirt MoonGlow

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    Vehicle:
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    Model:
    Two
    Replace battery with oem, then ask questions (if any)

    9 years is a long life for not much on the road.
     
    #2 dig4dirt, Jan 19, 2020
    SFO and jerrymildred like this.
  3. edthefox5

    edthefox5 Senior Member

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    Vehicle:
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    11.3 under load is all you need to see.

    And the reason its unhappy you don't drive much that will kill the 12 volt its basically siting in an uncharged or under charged state all the time and will sulphate which means it will never ever retain a full charge. Your mileage must be terrible also. It is also very hard on the hybrid battery. The prius's that do best with both these battery's are the cars that are driven a long ways every single day.

    The G2 Prius is a poor choice for the life your leading. It will many issues over the years. Your much better off with a good old combustible engine only car like a Corolla. Becasue the next thing that will go is the hybrid battery with a 2004 you are way over due for that.
     
    #3 edthefox5, Jan 19, 2020
    DKM and jerrymildred like this.
  4. jerrymildred

    jerrymildred Senior Member

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    Vehicle:
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    Two
    Welcome, DKM.

    That's not just possible, it's very probable. You might want a battery maintainer to keep it charged up. Not just a dumb trickle charger, but something smart enough that you can leave it connected indefinitely. Several people here use them.

    You abused the heck out of the OEM for nine years before it started failing. Why even think about another brand unless you'd like to be replacing batteries more often? I really like the one Toyota sells. Not the cheapest but worth it in the long run.

    Yeah, that's not the best use for a Prius. But I think a Prime (or a PiP) would be way better than a gasser. It would still need a tender for the 12V, but the car would only use gas on vacations. No vacations? Get a BEV.
     
    #4 jerrymildred, Jan 19, 2020
    DKM likes this.
  5. DKM

    DKM Junior Member

    Joined:
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    Location:
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    Vehicle:
    2004 Prius
    Model:
    N/A
    Thanks for the info everyone! It's nice to have confirmation on the battery.

    In regards to the OEM battery, would you know where I could find them in Canada?

    As I'm on a budget, I was also wondering if you all would know of any discounts associated with buying car parts/batteries. Like, for instance, I am aware membership to CAA can provide discounts on certain things. Just wanted to know if there are other membership benefits (i.e. Costco) that might help lower the cost of a brand new 12V battery? Just looking for tips if you have any.

    Thanks again everyone, your responses are much appreciated!
     
    #5 DKM, Jan 19, 2020
  6. jerrymildred

    jerrymildred Senior Member

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    Two
    Easiest place to find the OEM battery is the Toyota dealer. Dealer prices and integrity can vary wildly, so shop around. The on two miles from me is a good one, but that's a long way from you. :)
     
    #6 jerrymildred, Jan 20, 2020
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