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Could the wrong 12V battery cause warning lights?

Discussion in 'Newbie Forum' started by enna1985, Mar 1, 2021.

  1. enna1985

    enna1985 New Member

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    Vehicle:
    2003 Prius
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    Hi there,

    Looking for a bit of advice. Have a hand-me-down Prius and the warning lights (the triangle and car with exclamation point through the middle) keep coming on. The car starts and drives fine. At first it was only happening if I hadn't driven it for a few days or a week, but now it's happening any time. Sometimes turning the car on/off will reset it and it will go for a couple of days.

    I took it to the local Toyota to get someone to look at it a few months ago and they said they couldn't find a problem. After that it was OK for a month or so, but has been worse since.

    The only thing I can think of is that last year the 12V battery died. My sister needed the car and the Prius battery had a wait time of 6 weeks. Someone told her a normal lead acid battery would be fine and she could get it immediately, so she did that. Could a not-ideal battery cause the warning lights to be on?

    I'm sort of broke, been a helluva year, so can probably either afford the new battery or taking it in for someone to maybe be able to tell me if it actually needs a new battery, so just trying to see if anyone else has had a similar problem and has any ideas?

    I do not have a way to read the error codes currently. Contacted the place I took the car to last to ask if they had any error codes on record and they said they didn't think there were any. But then why would the lights be on?

    Thanks.
     
    Rudd likes this.
  2. Rudd

    Rudd Junior Member

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  3. bisco

    bisco cookie crumbler

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    exactly
     
  4. bisco

    bisco cookie crumbler

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    no, 12 volts is 12 volts.

    it may be that the battery needs a charge, or it may be something else.

    but if you have no tools, don't diy, and have no money, there isn't much we can do over the internet.
     
  5. ChapmanF

    ChapmanF Senior Member

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    Exactly. If those lights are on, there are trouble codes, and the codes will give us the best information about what might be going on with the car. Someone is going to have to read them.

    Around here, a lot of people are using an old beater Windows laptop and buying a cheap J2534 dongle to use with Techstream. There are a lot of threads about that.
     
  6. enna1985

    enna1985 New Member

    Joined:
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    Location:
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    Vehicle:
    2003 Prius
    Model:
    N/A

    Thanks, I might look into that. Was a bit thrown by the mechanic saying there were no error codes last time, because I took it to Toyota thinking they would be best placed mechanics to deal with a Prius. But no luck.

    Thanks everyone else, too. Have access to a garage full of tools and though I haven't looked at cars much I'm not unhandy generally. Just haven't had a lot of time lately to figure out what needs doing (a family member is having a major health crisis, has been in hospital for 6 months and all that entails). Also have money enough if something was likely to get a good outcome, but so far have been paying for mechanics to tell me they don't know what it is.

    Last time I took the car in for warning lights I had assumed it was the hybrid battery as it's fairly old and hasn't been replaced so far, but the mechanic said it didn't look like that. Hybrid battery seems to stay charged fairly well and haven't noticed any problems that would indicate it's fading. When I haven't been driving it much because of the warning lights the hybrid battery drops down to about half charged in the dash display - but quickly charges again with minimal driving.

    Was in touch with the Toyota mechanic I took it to last time and was told to bring the car back in, but since they said there were no codes last time, and they couldn't figure out what the problem was I'm not sure it's the best option.

    Will look at getting the codes one way or another. Thanks again.