1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Inverter water pump failure, and now better fuel economy?

Discussion in 'Gen 2 Prius Main Forum' started by SW03ES, Jul 25, 2010.

  1. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    Hey all,

    My wife called me frantically that her Prius had the CEL as well as the red exclamation mark on, I told her to stop driving it and went to meet her. We had the vehicle towed to Fitzgerald Toyota for service, which we are familiar with and have used many times before.

    The inverter water pump had failed, but the inverter was fine. The water pump of course is not covered under the Hybrid warranty and the car is out of powertrain warranty. Thats total BS IMHO, the inverter water pump is clearly a part of the hybrid system. I even asked them what would happen if I just did nothing and waited for the Inverter to fail since that WAS covered. They didn't really have an answer for me.

    Well $380 later she's on the road again.

    You may or may not remember, I have always thought something was wrong with our Prius because we never really got the mileage others were getting. 46MPG was the absolute top end even when being very careful. Since the repair, the mileage has been MUCH better. For the first time ever we are getting over 50 MPG, and we can now hear the fan running in the back for the battery packs which we NEVER heard before.

    Any ideas?
     
  2. chich2000

    chich2000 Junior Member

    Joined:
    Jan 22, 2006
    33
    0
    0
    Location:
    Surprise, AZ
    Vehicle:
    2006 Prius
    Mine failed at 40K and was replaced under warranty! I do have the extender warranty but the service manager specifically said it was covered under the hybrid warranty. Wonder if your dealer pulled a fast one on you? I really didn't notice an increase in mpg after the replacement but my A/C is always on in +110℉ heat in AZ. I has been over a year since it was replaced.
     
  3. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    Naa, with 40k and an '06 it was covered under the powertrain warranty. I called 5 dealers and checked on here as well as elsewhere online. The inverter water pump is definately covered under the powertrain warranty and not the hybrid warranty.

    But did you ever feel like I did that the mileage wasn't right before you had it fixed? I have a feeling the cooling system for the Inverter never worked right from day 1 on my car...makes me a little worried about the Inverter's lifespan. I had it in the shop several times back in '04 and they always said everything was operating as it should.

    In the winter our fuel economy gets in the 20s, we'll see how it does this year after this repair.
     
  4. usbseawolf2000

    usbseawolf2000 HSD PhD

    Joined:
    Sep 22, 2004
    14,487
    2,994
    0
    Location:
    Fort Lee, NJ
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Thanks, good to know. Do keep us posted with the MPG.

    Have you changed the 12V battery?
     
  5. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    I will.

    No I haven't changed the 12V battery, thats something that I have been meaning to do...
     
  6. Rokeby

    Rokeby Member

    Joined:
    Jan 21, 2008
    3,033
    708
    75
    Location:
    Ballamer, Merlin
    Vehicle:
    2008 Prius
    SWO3ES,

    I'm glad that you got things squared away for better MPGs in warmish
    weather -- lately I'd say temps have been more than warmish. A friend
    has wondered aloud, "Who left the thermometer on "Hell?" :p

    Is that a typo? This is not what I'd expect, unless:
    * OAT was around -10 degF, and/or
    * trips are only 4-5 miles long and the ICE/cat converter never get
    warmed up.

    Even at 30 degF, I usually see 45-50 MPGs on my 28 mi. daily round
    trip commute.

    I hope things get way better in the MPG department this winter.

    If you have any say in the matter, have who ever is in charge cut way
    back on the snowfall. :rolleyes:
     
  7. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    My idea is that the 12V battery was disconnected while your car was repaired. This gave the various ECUs a chance to power down and then power back up when power was restored and the car was started.

    If you are relying upon indicated mpg per the MFD, that also should reset when the 12V power has turned off. After the power is restored, the mpg readings are tentative and will become more precise as time passes. So, see whether the improved mpg continues over the next couple of months.

    Regarding the traction battery fan running at a higher speed than you've previously noticed, maybe the summer weather is hotter this season, or maybe the battery is starting to age so it has less capacity, which results in charging and discharging at a more rapid pace, which produces more heat.
     
  8. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    My wife does drive mainly short trips, but still I wouldn't expect the MPG would get down THAT low, and we're talking about temps in the 30s and 40s here.

    I will definately see what I can do ;)

    That could very well be the case, I'll keep watching it and report back.

    Also possible, but we had driven it out to dinner and my wife and I both said at the same time "What the hell is that?" and checked to see if the windows were open in the back. We definately have never heard it run before...ever...could be a coincidence...
     
  9. galaxee

    galaxee mostly benevolent

    Joined:
    Mar 14, 2005
    9,810
    464
    0
    Location:
    MD
    Vehicle:
    2005 Prius
    well, it is pretty damn warm around these parts lately, isn't it? if there's anything we can do to help, we're just a short zip down 270 from you now.
     
  10. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    Are you really? Welcome to the neighborhood! What brought on that change?
     
    1 person likes this.
  11. galaxee

    galaxee mostly benevolent

    Joined:
    Mar 14, 2005
    9,810
    464
    0
    Location:
    MD
    Vehicle:
    2005 Prius
    thanks! in short, we're here for the opportunities that were not present in our former location :)
     
  12. Canuck

    Canuck Member

    Joined:
    Aug 16, 2004
    605
    2
    0
    Location:
    Vancouver Island,BC,Canada
    Vehicle:
    2011 Prius
    Model:
    Three
    :cheer2:
    Perhaps either you or hubby are going into politics where you can have an opportunity to convince everyone to drive a Prius.
    In any case all the best in the new location.
    Gary
     
  13. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    Cool! Well if you ever need help finding those opportunities just let me know, I know a lot of people in a lot of different industries...
     
  14. timtim2008

    timtim2008 Member

    Joined:
    Jun 13, 2009
    204
    22
    0
    Location:
    Alpharetta, GA
    Vehicle:
    2004 Prius
    Model:
    N/A
    why there is no recall or class action for the inverter pump?
     
  15. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    Is it really that common a thing? Its not really unusual for a water pump to fail after 6 years, on the Lexus its normal to replace the pump after 90k miles just as a precaution because most of the labor is done for the timing belt anyways. Our actual water pump on the Prius failed at like 58k miles. The weird thing about the Prius is it has two water pumps.

    My only issue is that the inverter water pump should rightfully be a part of the hybrid warranty...
     
  16. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Actually the 2G NA Prius has four coolant pumps:

    1) mechanical engine coolant pump that is powered via the serpentine belt

    2) electric engine coolant pump that circulates coolant when the engine is not running, for the sake of keeping cabin heating working. (BTW, I have not seen any posts here, about this pump having failed. However you do see people complaining about lack of cabin heat in the winter. My guess is that some of these complaints are attributable to a bad electric pump.)

    3) electric coolant heat recovery system pump, this makes plenty of noise when you turn on and turn off the car so it is obvious when that pump is working

    4) electric inverter coolant pump, and I agree it would be reasonable for that to be covered under the 8 year / 100K hybrid system warranty. Nevertheless, it is not.
     
    2 people like this.
  17. SW03ES

    SW03ES Senior Member

    Joined:
    Dec 8, 2004
    2,480
    176
    0
    Location:
    Gaithersburg, MD
    Vehicle:
    2004 Prius
    Oh Good, so I have two more to worry about ;)
     
    1 person likes this.
  18. cwerdna

    cwerdna Senior Member

    Joined:
    Sep 4, 2005
    12,544
    2,122
    1
    Location:
    SF Bay Area, CA
    Vehicle:
    2006 Prius
    Woah! I didn't realize about #2.

    I've had #3 replaced under warranty (TSB, IIRC) because it was intermittent squealing on start up or shutdown.
     
  19. andyprius

    andyprius Senior Member

    Joined:
    Feb 21, 2005
    2,212
    188
    0
    Location:
    Sacramento, California.
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Hi Pat, Are you saying in your 1st para, that it may be a good procedure to recycle the computers from time to time? My Prius is also getting 5mpg less than previously. ty andy
     
  20. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Hi Andy,

    What had your mpg been last summer, and what is it now?

    Actually I was saying that the indicated mpg calculation per the MFD is refined as time passes, after 12V power has been restored. I'm not saying that the true mpg is actually better.

    Since you think that your mpg has worsened, have you checked the usual suspects such as tire inflation pressure, wheel alignment, parking brake drag, and engine oil level? Does the car need new iridium spark plugs, an engine air filter, and throttle body cleaning?

    It doesn't hurt to remove 12V power, wait several minutes, then restore power. However I don't know that this would help your particular problem.