Prius has 2 coolant reservoirs?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by randomwalk101, Mar 16, 2016.

  1. randomwalk101

    randomwalk101 DYI'er

    Joined:
    Feb 4, 2012
    532
    271
    0
    Location:
    texas
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I've never seen car with two coolant reservoirs like this one. What's the purpose of having 2?
     
    #1 randomwalk101, Mar 16, 2016
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,656
    50,849
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    the second one cools the inverter. it's because you have two power sources.
     
    #2 bisco, Mar 16, 2016
  3. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    23,055
    12,254
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    For the inverter, which needs to be kept at a different temperature than the ICE for efficiency and reliability. One of the possible advantages of the new semiconductors, that should be in the gen5, is that the system can got to one cooling system for the ICE and inverter.
     
    #3 Trollbait, Mar 16, 2016
  4. randomwalk101

    randomwalk101 DYI'er

    Joined:
    Feb 4, 2012
    532
    271
    0
    Location:
    texas
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Ahhh....I see. Btw if you're living in warm climate (like me, I'm in Houston), you may want to do a coolant to throttle body bypass. This is to keep your air temp low to increase efficiency. You won't won't feel a diff bc the increase is small but every bit helps I guess.
    The coolant to TB is to keep it from freezing up in the cold climate in the winter. Not an issue here in Texas/Florida/Arizona/etc.
     
    #4 randomwalk101, Mar 16, 2016
  5. JimboPalmer

    JimboPalmer Tsar of all the Rushers

    Joined:
    Apr 14, 2009
    12,470
    6,875
    2
    Location:
    Greenwood MS USA
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    There are in fact two completely separate cooling systems, one for the engine, and one for the inverter.

    If you watch this video on the Gen 2, the inverter cooling passages and electric water pump are featured at 9:40 to 10:35

     
    #5 JimboPalmer, Mar 16, 2016
    NutzAboutBolts likes this.
  6. MamaMango

    MamaMango New Member

    Joined:
    Oct 15, 2022
    1
    0
    0
    Location:
    Georgia
    Vehicle:
    2008 Prius
    Model:
    Base
    I need to replace the engine coolant reservoir, NOT the inverter reservoir. I’m having a terrible time finding the right part. Car is a 2008 Prius.
    can someone give me the part number? When I do a search I keep getting one for the inverter system. Thanks!
     
    #6 MamaMango, Oct 15, 2022
  7. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    26,039
    17,010
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Toyota doesn't seem to sell that bottle separately from the cooling fan shroud, callout 16701 below, part number 16711-21100.

    [​IMG]


    Salvage yard?
     
    #7 ChapmanF, Oct 15, 2022
(You must log in or sign up to post here.)