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

Low mpg, no little green cars

Discussion in 'Gen 2 Prius Main Forum' started by PriusOwner2017, Jul 20, 2017.

  1. PriusOwner2017

    PriusOwner2017 New Member

    Joined:
    Jul 20, 2017
    9
    2
    0
    Location:
    Nashville
    Vehicle:
    2004 Prius
    Model:
    N/A
    Hi! First time poster. I couldn't find any threads to answer this question but please forgive me if this has already been answered.

    I have a 2004 Prius with 148,000 miles. Yesterday I noticed some weird activity.

    A few things- I was recently involved in a car accident that was relatively low impact but resulted in the rear bumper being torn completely off (side swiped by a trolley.) So I'm driving the car with no rear bumper until it gets fixed. I wouldn't think this would effect the engine but just wanted to be clear.

    Secondly, I was out of town for about 10 days shortly after the accident, during which time the car sat in the driveway completely unused. I probably drove the car ~300 miles between the accident occurring and going out of town.

    Yesterday, having returned from my vacation, I hopped in the car and drove to a bakery about 2 miles from home with no problems. After a 10 minute stop, I turn on the Prius and suddenly get the big red triangle, plus the (!), VSC, and Check Engine lights on the dashboard. I immediately drive the car (which is running fine) to the neighborhood mechanic.

    The mechanic runs a diagnostic that says the hybrid battery needs to be replaced but suspects that maybe the car is acting funny because it was sitting for 10 days. He clears the codes and tells me to drive it around and see if the dashboard lights come back on. If not, then the car is ok.

    I drive all over town the rest of the day with no red triangle or any sign of distress from the car at all. It's running well except I notice that the gas mileage is very low, around the 25-30 mpg range. Watching the screen, I notice that almost no leafy green little 50 wh cars are being generated. The hybrid engine seems to only engage when I'm coasting with my foot completely off the gas pedal.

    I went into diagnostic mode last night to check the 12v battery. It's definitely in good shape.

    What is the issue here and will it be (gulp) very expensive to fix?
     
    #1 PriusOwner2017, Jul 20, 2017
  2. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,470
    8,383
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    Your issue is a bad hybrid battery, resetting the car doesn't fix. It'll come back real soon.
     
    #2 JC91006, Jul 20, 2017
  3. fotomoto

    fotomoto Senior Member

    Joined:
    Apr 22, 2009
    5,597
    3,771
    0
    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    Yes your HV battery is about dead. It's very weak so it's not contributing as much to propulsion and the gas engine (ICE) is having to work harder to compensate thus the poor MPG. The ICE can only do so much so when the battery fails, the car will be in "turtle mode" with very little power.

    Sitting for 10 days was what tripped it to finally fail and cause the warning lights.
     
    #3 fotomoto, Jul 20, 2017
  4. PriusOwner2017

    PriusOwner2017 New Member

    Joined:
    Jul 20, 2017
    9
    2
    0
    Location:
    Nashville
    Vehicle:
    2004 Prius
    Model:
    N/A
    Dang! Well, I guess that answers my last question... this will likely expensive, yes? A full hybrid battery replacement is going to be required?
     
    #4 PriusOwner2017, Jul 20, 2017
  5. PriusOwner2017

    PriusOwner2017 New Member

    Joined:
    Jul 20, 2017
    9
    2
    0
    Location:
    Nashville
    Vehicle:
    2004 Prius
    Model:
    N/A
    Also, is there any conceivable way that the accident damaged the battery? The at-fault party's insurance has still not completed an estimate of the repair cost.
     
    #5 PriusOwner2017, Jul 20, 2017
  6. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,470
    8,383
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    You can try billing them for it, as it died sitting from non use
     
    #6 JC91006, Jul 20, 2017
  7. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    11,312
    3,588
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    Other Hybrid
    Model:
    N/A
    The main thing is the 12v battery tends to get discharged during any kind of shop work. also it is in the rear where you're bumper is so you might want to make sure it was not damaged.
     
    #7 wjtracy, Jul 20, 2017
  8. fotomoto

    fotomoto Senior Member

    Joined:
    Apr 22, 2009
    5,597
    3,771
    0
    Location:
    So. Texas
    Vehicle:
    Other Hybrid
    Price wise, your options vary greatly.

    DIY repairing a failed module or two=$50-100. Can last from a few weeks to a 12-18months (the latter unlikely on a 2004 batt)
    A refurbished battery=$700-3,000. Warranties vary from 90 days to 3 years. These use old but still good modules from other failed packs to make one good pack. Frequent warranty claims so the company is important.
    New battery from Toyota=$2,100-4,000 depending on dealer pricing and labor. 1-4 year warranty but should be good for 10+ like the original.
     
    #8 fotomoto, Jul 20, 2017
  9. wjtracy

    wjtracy Senior Member

    Joined:
    Sep 19, 2006
    11,312
    3,588
    1
    Location:
    Northern VA (NoVA)
    Vehicle:
    Other Hybrid
    Model:
    N/A
    Also could be brake actuator issue which is covered to Dec_2017

    Are we talking about a Toyota "mechanic" which helps sometimes.
     
    #9 wjtracy, Jul 20, 2017
  10. Moving Right Along

    Moving Right Along Senior Member

    Joined:
    Dec 29, 2016
    687
    539
    0
    Location:
    USA
    Vehicle:
    2009 Prius
    Model:
    N/A
    As wjtracy said, the 12v battery is very close to the rear bumper, so it could have been damaged in the accident. The hybrid battery is behind the back seat and under the carpet in the hatchback storage area. From your description of the accident, it seems unlikely that the hybrid battery was damaged from the impact, but you could possibly make the argument stated by JC91006 that it died as an indirect result of the accident.
     
    #10 Moving Right Along, Jul 20, 2017
  11. PriusOwner2017

    PriusOwner2017 New Member

    Joined:
    Jul 20, 2017
    9
    2
    0
    Location:
    Nashville
    Vehicle:
    2004 Prius
    Model:
    N/A
    I'm thinking my best options are either 1) hope for a total loss on the vehicle due to the body damage and just buy a new car or 2) get a local hybrid shop to rebuild the battery (6 month unlimited milage guarantee.)
     
    #11 PriusOwner2017, Jul 20, 2017
  12. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,470
    8,383
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    Do you have a sledge hammer? The car's valuation is pretty low, so maybe $3000 damage would total it
     
    #12 JC91006, Jul 20, 2017
    bisco likes this.
  13. Ellen Berman

    Ellen Berman Junior Member

    Joined:
    Jul 19, 2017
    16
    5
    0
    Location:
    Wilmington, de
    Vehicle:
    2007 Prius
    Model:
    Three Touring
    I have a 2007 touring with 168,000. My mpg dropped to 38. I unhooked the positive cable on regular battery..reattached, changed spark plugs, changed oil. MPG jumped.. to almost 44. Guy at dealership suggested the cable thing. Resets sll electronics.. seemed to do the trick. Checked 12v and got higher than 13 reading. Just thought I'd jump in on this conversation.

    Posted via the PriusChat mobile app.
     
    #13 Ellen Berman, Jul 20, 2017
    bisco likes this.
  14. davecook89t

    davecook89t Senior Member

    Joined:
    May 10, 2016
    1,057
    789
    0
    Location:
    Washington State, Florida
    Vehicle:
    2017 Prius
    Model:
    Four Touring
    MPG can be affected by so many things, I would think it's not a good indicator of hybrid battery health. Rapid fluctuation of State of Charge of the hybrid battery on the display under light load conditions is still the best indicator that the hybrid battery is near failure.
     
    #14 davecook89t, Jul 20, 2017
    Ellen Berman likes this.
  15. Ellen Berman

    Ellen Berman Junior Member

    Joined:
    Jul 19, 2017
    16
    5
    0
    Location:
    Wilmington, de
    Vehicle:
    2007 Prius
    Model:
    Three Touring
    The 95 degree weather could play a part as well.

    Posted via the PriusChat mobile app.
     
    #15 Ellen Berman, Jul 20, 2017
    bisco and davecook89t like this.
  16. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,693
    48,945
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    check the 12v with the car off, after it has been off overnight.
     
    #16 bisco, Jul 20, 2017
    Ellen Berman likes this.
(You must log in or sign up to post here.)