Low Voltage in Rear Power Outlet

Discussion in 'Prime Technical Discussion' started by PiPLosAngeles, Nov 27, 2018.

  1. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    That is the message from corporate Toyota. They say the manufacturer simply doesn't have any of the batteries, so nothing they can do. Still no battery.
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    73,886
    30,483
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    brutal. good the it is strong enough to start the car
     
  3. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    It reads 12.5V when the car is off, so I guess that's all it needs. Once the car is in READY it's 14.5V. I really don't think the battery is the cause of the low voltage in the 12V outlets since it happens when the car is in READY mode and the voltage at the battery is 14.5V and the voltage at the unused outlet is about 13.5V. There is some source of resistance between the battery and the outlet consistent with 22 AWG wiring. Since both outlets are exactly the same, I doubt it's just a loose connection.

    I keep meaning to test the voltage at the fusebox, but I haven't got around to it.
     
    SteveMucc likes this.
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    73,886
    30,483
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
  5. SteveMucc

    SteveMucc Active Member

    Joined:
    Oct 3, 2017
    357
    237
    0
    Location:
    Kentucky
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Does the voltage change if the car is in force charge mode?
     
  6. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    What is force charge mode? Do you mean forcing ICE to run to charge the traction battery?
     
  7. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    So, it's been a week today since I've heard from Toyota about this issue despite the case manager's promise to to call me last Tuesday with a status update. Last Monday he told me that the battery manufacturer had some new stock that they'd be shipping by Tuesday the 11th. The dealership still doesn't have any batteries, none on the way, and they still report that they cannot get an ETA from the supplier. When I called Toyota this morning they tell me the case manager isn't available and all I can do is wait for his call. There is no manager or anyone else to speak with and requests to transfer the case to another case manager have to go through the current case manager.

    Since my previous four Toyotas have never had a single issue, I have no way to judge if this appalling service is the norm for Toyota. I expect this kind of runaround and lackadaisical attitude towards customer service from the DMV, but I would have never expected it from Toyota based on my past experiences.
     
  8. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    73,886
    30,483
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    i guess you haven't spent enough time here reading others complaints :cool:
     
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    73,886
    30,483
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    force charge is available when the car is moving to charge up the hybrid battery as much as 80% if desired.
    you would have to have someone measure the outlet voltage while you drove.
    not really sure what it would accomplish
     
  10. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    It's hard to tell online whether someone is "that" customer that flies off the handle for the tiniest inconvenience, or whether it's legitimate customer service failings. The lack of proper 12V power is a major issue for someone who has to be able to work out of their car, but it doesn't rise to the level of making the car worthless for its intended purpose. I wouldn't say I'm angry, and I'm not raising my voice at anyone or saying anything rude. I'm just disappointed that Toyota sold me a brand new car that they acknowledge has a real bona fide problem, and they just seem like they can't be bothered to do anything about it (or even call when they promise).
     
  11. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    73,886
    30,483
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    first of all, a dealer is not toyota. but toyota is responsible for bad batteries, defective parts and designs, and inventory on a national level

    i agree that it is sometimes difficult to make judgements on the internet. you have been fortunate not to have had any past problems.
    i have a stack of recalls a mile high.
     
  12. SteveMucc

    SteveMucc Active Member

    Joined:
    Oct 3, 2017
    357
    237
    0
    Location:
    Kentucky
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I was curious if it could be related to the inverter. That may well function differently if it's being supplied from the MG vs the battery alone).
     
    bisco likes this.
  13. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    73,886
    30,483
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    would it be different than hv mode?
     
  14. SteveMucc

    SteveMucc Active Member

    Joined:
    Oct 3, 2017
    357
    237
    0
    Location:
    Kentucky
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    don't know. when it's in hv mode it's constantly moving energy back and forth to/from battery. From what I "feel" (from casual observation), CHG mode seems to run the engine at a higher rpm than what it would normally be, so that it's seems to be always charging the battery rather than in a constant state of flux. that would seem to guarantee you more that you're putting power into the battery rather than taking it out (otherwise you're stuck staring at the energy flow screen trying to keep the car at a point where it's putting energy into the battery and keeping the engine running (which isn't always easy to do)).
     
    bisco likes this.
  15. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    So I've been driving the last two weeks without using the 12V outlets. On whim I decided to test them today. Low and behold, under load they're at 12.6V. Now I'm thinking the battery's built up a charge and it can keep the load up. BUT, there's something in the owner's manual that concerns me: page 719 says:

    [​IMG]

    If 5A is the max charging current, what happens if you're drawing 20A (the max on each outlet) for a two-hour drive? I sure hope the DC-DC converter isn't limited to 5A, because that would be ridiculous. You'd run the 12V dead in a couple of hours and it would take 10 or more hours of not using any 12V power to charge it back up.
     
  16. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    I know it probably means that when using a 12V charger to charge the battery you should limit to 5A, but I can't help but wonder if there's something to it. I'll start using the 12V outlets again and see if it runs the battery down over time.
     
  17. Elektroingenieur

    Elektroingenieur Senior Member

    Joined:
    Jan 8, 2017
    948
    1,377
    9
    Location:
    California
    Vehicle:
    2016 Prius
    Model:
    Three Touring
    According to the New Car Features book, the maximum output current for the DC-DC converter is 100 A.
     
  18. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    I'll test what happens. Hopefully the battery is now charged all the way and everything's honky dory. If everything stays good after a week or so of using the 12V outlets I'll chalk it up to a headache caused by a 12V battery that wasn't maintained on the lot. I really, really want that to be all it is.
     
  19. Dale Leonard

    Dale Leonard Member

    Joined:
    May 16, 2017
    66
    46
    0
    Location:
    Hartland, Wi
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    It is a bad battery. Go see if you can find a deep cycle battery that fits. Trolling motor battery.
     
  20. PiPLosAngeles

    PiPLosAngeles Active Member

    Joined:
    Nov 18, 2012
    477
    123
    0
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Plus
    Me and my big mouth. As soon as I threw the car into drive the voltage dropped below 10.5V again. For the first time, I was testing at night so I noticed that when you throw the car into drive the interior lights dim noticeably, so it's not just the wiring to the outlets - it's the whole 12V system. The voltage in the 12V outlet with the 6A load drops from 12.6V to 10.5V at the same time. Back at square one.

    Trying to find one. It looks like the OEM Chevy Spark battery is the same size (LN1), but no one has one of those in stock either. I'm getting close to just trying any old battery I can find (even if it doesn't fit) just to see if it cures the issue.
     
    #60 PiPLosAngeles, Dec 23, 2018
    Last edited: Dec 23, 2018
Loading...