Multiple codes on new prius

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by DomMole, Jun 29, 2026 at 2:41 PM.

  1. DomMole

    DomMole New Member

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    Hello all, new to the forum and was recommended to ask here by several other prius owners:

    Just picked up a 2005 Prius that had been sitting for a few months for a good deal, clean title and 195k miles with a brand new hybrid battery with dealer verified install paperwork. Only issue is it has the red triangle of death (exclamation light and VCS light) and was showing P0A08 and P0A09 codes. Drove it home 50 miles, car ran flawlessly with no issues. Figured the codes were related to the 12v battery after it had been sitting for a few months. Swapped the battery when I got it back to my house, codes did not clear and two new codes (P3190 and P3191) came on along with the CEL. Car has not failed to start up once, no idea what could be causing these. Again, car drove flawlessly on the way to my house. Any advice or possible next steps are greatly appreciated. All I've done so far is make sure it had gas in it and replace the 12v battery.
     
    #1 DomMole, Jun 29, 2026 at 2:41 PM
  2. pasadena_commut

    pasadena_commut Senior Member

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    The first two mean the DC-DC converter isn't working, and in particular, that it probably isn't charging the 12V battery. Measure the voltage on that (at the jump point under the hood will be fine) and tell us what it is when the car is off and when it is on. The second two codes often mean the ICE isn't starting at all. That can happen if the HV battery is nearly fully discharged. Hard to see how that could be right if you are able to drive it around though.

    If you have a decent OBD2 dongle then you could read the pack voltages using an app like Dr. Prius or Torque Pro. Do that soon and report them back here.

    Guessing, because there is not all that much info to work with yet, I would suspect the "new hybrid battery" isn't working right. If it is a name brand aftermarket (Green Bean or something like that) they should be willing to check it out under warranty. What was the source of this vehicle? Dealer, used car dealer, private sale?
     
    #2 pasadena_commut, Jun 29, 2026 at 8:55 PM
  3. bisco

    bisco cookie crumbler

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    are you sure the engine is starting? have you tried driving it again?
     
    #3 bisco, Jun 29, 2026 at 9:05 PM
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