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2010 Prius - Won't start - new 12v battery

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Nick Pi, Jan 16, 2024.

  1. Nick Pi

    Nick Pi New Member

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    Hello everyone. My name is Nick and I'm new to this group.

    What I have is a 2010 Prius with 216k miles on it that for the first time in it's life will not start. The 12 volt battery was old so I replaced it yesterday. After replacing the battery: all lights are on, all dash lights come on, it beeps like it normally does while starting up, and when I push the button I can hear clicking (4 clicks I believe) from the hatchback area but it gave me nothing. After trying this process several times the "Low Traction Battery" message was displayed. Fast forward to today: Hooked a code reader up to it and it provided the P0401 (Exhaust Gas Recirculation Flow Insufficient Detected). While waiting for the code reader to complete the process the screen also started flashing the "Check Hybrid System" warning.

    Can the P0401 code be connected to the car not starting? Can the HV battery be bad despite the P0A80 code not being presented?

    One more piece of information that might/might not be important. It has been cold here the last few days with real temps dropping to around -15F in the mornings.

    Where should I go from here? Any input is greatly appreciated.
     
    #1 Nick Pi, Jan 16, 2024
  2. PriusCamper

    PriusCamper Senior Member

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    That EGR code probably happened a while ago, I doubt its related to your cold weather glitch. Perhaps your new 12v has been sitting on shelf for a while and isn't fully charge combined with low temps... Take it back to place you bought it from and have them charge it. Or if you have at least a 10amp smart charger, bring it inside and charge it. Also check your orange hybrid battery service plug, sometimes the slider that's the final locked position for it gets bumped during 12v battery work.
     
    #2 PriusCamper, Jan 17, 2024
  3. Tombukt2

    Tombukt2 Senior Member

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    Do you mean engine doesn't start as in you hear the engine running or are you talking about the word ready not being displayed and you can't put the car in gear do anything? If the car readies the word r e a d y is displayed and you put it in reverse to back out of your parking space or forward as the case may be the car won't move it won't do anything?
     
    #3 Tombukt2, Jan 17, 2024
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    Off-topic, but EGR triage nurse here:

    Have you had it since new? Is engine coolamt level stable?

    There’s a good likelihood the EGR system (including intake manifold EGR passages) is completely carbon-blocked. Unfortunately the head gasket may be leaking coolant into combustion chambers too, which will eventually bend a piston arm.

    see first 2 links in my signature; on a phone turn it landscape to see signature.
     
    #4 Mendel Leisk, Jan 17, 2024
    Last edited: Jan 17, 2024
  5. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Your 12v battery boots the computers and closes some relays to allow the traction battery to do the real work.

    The traction battery has discharged too much to be able to start the engine.

    It is possible to charge the battery from a mains source, but it isn't easy. Toyota has a charger that can do the trick, but most dealers don't keep it around- they fedex one in as needed, which isn't terribly cheap.

    You can modify some sorts of hobby and industrial battery chargers to do what needs to be done, if you are electrically adventurous and handy.
     
    #5 Leadfoot J. McCoalroller, Jan 17, 2024
  6. Nick Pi

    Nick Pi New Member

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    Thank you for replying. Will do both of these things today.

    Hello. The engine doesn't start. The word "ready" was blinking but went away.

    Hello sir. In response to your two questions: I purchased the vehicle in 2014. Engine coolant level is currently stable and hasn't been an issue since owning it.

    Hello. Thank you for this information.
     
    #6 Nick Pi, Jan 17, 2024
    Last edited by a moderator: Jan 17, 2024
    Mendel Leisk likes this.
  7. PriusCamper

    PriusCamper Senior Member

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    That sounds like a great description for some of my social media profiles! Thanks!
     
    #8 PriusCamper, Jan 17, 2024
  8. ASRDogman

    ASRDogman Senior Member

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    Try charging the 12v battery. It's very likely too low.
    They do not keep the batteries charge. Charge and 4 amps or less for at least 8
    hours, longer if possible.
    4 hours at 4 amps should be enough to test and see if it will get the system started.

     
    #8 ASRDogman, Jan 17, 2024
  9. Nick Pi

    Nick Pi New Member

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    Thanks for taking the time to reply here.
    Battery is on the charger now.
     
    #9 Nick Pi, Jan 17, 2024
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  10. ASRDogman

    ASRDogman Senior Member

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    You're welcome. Let us know is that resolved the problem.

     
    #10 ASRDogman, Jan 18, 2024
  11. Nick Pi

    Nick Pi New Member

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    Ok, here's where I'm at today.
    -Fully charged battery in and verified that all connections are secure.
    -Checked the orange service plug and it is locked.
    -It went to a full "Ready" mode.
    -Display showed the hybrid battery at 5 bars when getting in the car and dropped to 1 bar upon trying to start.
    -Twice it sounded like power made it to the engine but not enough that it started. Almost like the power made it's way up there but wasn't strong enough to continue, or something stopped it, if that's makes sense. I tried to start it several times and this only happened on the first try and after it set for a few minutes between attempts.
    - "Low Traction Battery" or "Check Hybrid System" are not present today.
    -Hooked the code reader up again and received the P0401 code in addition to a U0293 code.
    -Still won't start.
     
    #11 Nick Pi, Jan 18, 2024
  12. Mendel Leisk

    Mendel Leisk Senior Member

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    That doesn’t sound good; 1 bar never happens normally.
     
    #12 Mendel Leisk, Jan 19, 2024
  13. ASRDogman

    ASRDogman Senior Member

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    Have you tried clearing the codes? And possibly disconnecting the 12v battery for 30 minutes.
    I'm certain someone else with respond with some help.
    Maybe remove the orange safety switch and reinstall it.
     
    #13 ASRDogman, Jan 19, 2024
  14. Brian1954

    Brian1954 Active Member

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    Do you have any warning lights on when you try to start the car?

    What code reader are you using? Most of them are not capable of communicating with all the different ECUs that are in a Prius, so you might not be reading all the trouble codes that your car has.
     
    #14 Brian1954, Jan 19, 2024
  15. Nick Pi

    Nick Pi New Member

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    I have not tried clearing the codes. I will do so as well as disconnecting the battery and reinstalling the safety switch. Thanks again. Will report back.
     
    #15 Nick Pi, Jan 20, 2024
  16. Nick Pi

    Nick Pi New Member

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    Hello.

    I am using the Zurich Bluetooth code reader: ZR-BT1 OBD2 BLUETOOTH Dongle Code Reader

    When trying to start the car the following warning lights are displayed:
    • BRAKE
    • ABS
    • Check Engine
    • Electric power steering warning light
    While waiting for the code reader to complete a cycle the hybrid battery charge level indicator drops from 4-5 bars to 1 bar and after a couple of minutes the warning messages below are displayed:
    • CHECK HYBRID SYSTEM
    • P LOCK MALFUNCTION WHEN PARKING, PARK IN FLAT PLACE AND APPLY PARKING BRAKE SECURELY
    Thank you for your time.
     
    #16 Nick Pi, Jan 20, 2024
  17. Nick Pi

    Nick Pi New Member

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    I just followed the steps you suggested in clearing the codes, unhooking the 12v for 30 minutes, and unhooking and reinstalling the orange safety plug. The attempt to start gave the same result as prior. After doing so I re ran a scan with the code reader and the one code that pulled up was P0401 (EGR).

    While waiting for the code reader to complete a cycle the hybrid battery charge level indicator drops from 4-5 bars to 1 bar and after a couple of minutes the warning messages below are displayed:
    • CHECK HYBRID SYSTEM
    • P LOCK MALFUNCTION WHEN PARKING, PARK IN FLAT PLACE AND APPLY PARKING BRAKE SECURELY
    Thanks again for replying here to me.
     
    #17 Nick Pi, Jan 20, 2024
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