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Code 3125 no start.

Discussion in 'Generation 1 Prius Discussion' started by vaughnstark777, Oct 29, 2014.

  1. vaughnstark777

    Joined:
    May 4, 2012
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    Location:
    Roy, WA
    Vehicle:
    2001 Prius
    Model:
    I
    I bought a 2003 that I was told was running it wasn't but it was cheap and only had 128000 miles on it so I bought it anyway.
    When I turn the key I here what sounds like the MG1 wants to engage but then nothing. Checked the codes, got 3125, cleared it, tried again, same thing. 12v battery is strong and everything 12v, PS, PB, lights etc., work fine with the key on so I don't suspect an inverter problem, but I admit I am not an expert so I'm willing to be schooled.
    I don't have a scan tool that will give me sub codes but since this is gen 1 number 3, I also have 2 2001's that my wife and I drive, maybe I should look into purchasing one.
    (n)
    I have an extra CVT out of a 2003, that was t-boned, that I know is good and I can swap it out if that is what I need to do.
    But before I do that is their anything else I should test to make sure I am on the right track?
     
  2. bisco

    bisco cookie crumbler

    Joined:
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    Location:
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    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    i would get the scanner first, or stop by auto zone and get the codes read.
     
  3. vaughnstark777

    Joined:
    May 4, 2012
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    Location:
    Roy, WA
    Vehicle:
    2001 Prius
    Model:
    I
    I got a basic scanner and I keep getting a 3125. And as I said in the subject heading, it doesn't start, so I'm not able to take it anywhere without paying a hefty tow charge there and back. I have checked some other threads on this subject but have found some differences in the details and am not sure if they were having precisely the same problem. But as I say it is a new problem for me.
     
  4. bisco

    bisco cookie crumbler

    Joined:
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    Plug-in Base
    ya, the basic scanners won't work on a prius, you need a scan gauge type minimum, or mini vci and tech stream best.
     
    bwilson4web likes this.
  5. ericbecky

    ericbecky Hybrid Battery Hero

    Joined:
    Mar 12, 2004
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    Location:
    Madison, Wisconsin
    Vehicle:
    2005 Prius
    Model:
    Two
    Get Mini Vci. For any in depth work it is necessary.
    Does the car go into Ready mode?
    Is there any engagement at all. Like a ka-klunk-a-klunk when you turn the key.
    Put a socket on the crank nut. Does the engine spin freely?
    Is there spark?
    Any other dash lights lit, like the triangle?
    Is it getting fuel? Remove back seat and see if you hear fuel pump running. Or check fuel pressure with a gauge.
     
  6. royfrontenac

    royfrontenac Member

    Joined:
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    Location:
    Kingston Ontario Canada
    Vehicle:
    2001 Prius
    Model:
    N/A
    In my 2001 manual it indicates 2125 has 20 sub codes that identify the problem in more detail. 3125 appears to be problem of inverter as far as service manual goes. Get minivic plus xp computer to troubleshoot further.

    Roy from Canada