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No voltage on hybrid battery

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Jayjaybobo, Oct 11, 2023.

  1. Jayjaybobo

    Jayjaybobo New Member

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    Hi guys, i have Prius 2015 i got the battery reconditioned it was all good but when i put battery back there is still message “ check hybrid system” I suspect the is no voltage coming in the inverter so i measured it and yes there is no output voltage at the port that go back to the inverter. Could something failed in junction box?
    Thanks all.
     
  2. Tombukt2

    Tombukt2 Senior Member

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    You're measuring what's going up to the inverter back at the battery right? I don't think you can do this with the safety plug removed you'd have to have the battery completely live and I guess what turned on or attempt to ready so the relays open and then you would measure the voltage on the car side heading to the inverter. And you're saying under those conditions you have no votes and reconditioned pack and so on and so forth we don't have some kind of connection correctly somewhere I do believe maybe it's because the safety plug is out? All the guys that spend their time doing this will be a long shortly with a lot of info.
     
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  3. Jayjaybobo

    Jayjaybobo New Member

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    Yes i have the safety plug in, no voltage on the car side head back to inverter.
     
  4. Tombukt2

    Tombukt2 Senior Member

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    Do the two relays click when you turn on the car is the voltage clearing the relays and getting lost from the relays output side to the front of the car or the battery's making no power at all any kind of way well what's the battery wired wrong I don't even know how you could do this but the junction block you mean the black thing next to the computer Do you have 211 volts anywhere or close to it 180 90 something.
     
  5. Jayjaybobo

    Jayjaybobo New Member

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    I did not hear the relays click at all meaning no power from the battery to the inverter as there is no voltage. Yes i do have high voltage from the battery connection point ( measured directly from series connector + - on both side) yes i mean the junction box next to battery it could be failed or something? Because the battery do have high voltage but after going thru the junction box there is no voltage ( measured + - on the connection that goes back to the head inverter in front of the car while safety plugged in ) i also check the continuity on the safety plugs to make sure it works, it works.
     
  6. Jayjaybobo

    Jayjaybobo New Member

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    This is the illustration i just made.
     

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  7. Mr. F

    Mr. F Active Member

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    Just checking boxes here, is the safety plug inserted correctly?

    One has to push it in, flip the latch down, and then slide the latch to the right until it clicks into place. Without this, the high-voltage battery is split into two disconnected not-as-high-voltage batteries measuring 136.8 V (19 modules) and 64.8 V (9 modules), but the voltage measured across the complete 28-module pack will be 0 V because there is a break between the 19-module battery and the 9-module one.
     
    #7 Mr. F, Oct 13, 2023
    Last edited: Oct 13, 2023
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  8. Tombukt2

    Tombukt2 Senior Member

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    Yes you got to have the plug in right so if you lift those two orange wires in the junction box you have voltage on each of those orange wires it's just not getting to the wire stud that goes to the inverter in the front of the car then I guess you've narrowed it down to that black junction box that sounds like I would think of course it can go bad. But it's probably one of those rare occasions or one of those things that doesn't go bad very often.
     
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  9. Jayjaybobo

    Jayjaybobo New Member

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    Yes i am sure the safety plug is sit correctly ( plug in , latch to the right and slide it back to the left). I do have voltages in those 2 split modules but 0 voltages at 2 wire studs thats why I suspect either junction box or the fuse blown in the safety plug ( does the safety plug have fuse in there? I don’t know) . Either way I already ordered both junction box and safety plug. I will install it and report back my last hope before towing to repair shop. I really appreciate you guy.
     
  10. Mr. F

    Mr. F Active Member

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    While you may be doing it the right way in reality, this description is not correct, and performing it as you have described will not complete the circuit. At no point do you slide it to the left.

    The correct steps are:
    1. Push the service plug in.
    2. Flip the latch down.
    3. Slide the latch to the right.
    Video here:
     
  11. Jayjaybobo

    Jayjaybobo New Member

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    Sorry for the confusion i mean left and right of the car, yes i did that correctly as video.
     
  12. Tombukt2

    Tombukt2 Senior Member

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    But you have voltage on the orange wires going to that black box If those orange wires are live and they plug into the black box and nothing comes out I would think something in the black box is not doing some kind of switching I would think that would be correct but the safety plug definitely has to be in correctly.