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

acceleration lag + atypical Battery Cooling Fan

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by coyote2, Sep 26, 2021.

  1. coyote2

    coyote2 Member

    Joined:
    Jun 29, 2004
    123
    29
    0
    Vehicle:
    2005 Prius
    Model:
    Two
    Today after sitting for 75 minutes in 70F weather, when I powered on the car the Drive Battery Cooling Fan turned on. It only does that right after I've driven it hard on the freeway, not after sitting (before sitting it had dome ten minutes of only moderate freeway driving).

    Then merging onto the freeway nearly floored, acceleration 'surged', by which I mean that instead of a smooth acceleration I got lags and kept to 60 mph. These lags only lasted about five minutes.

    On the way home I started the car again (no fan this time), freeway-merged and accelerated hard (as much as 0 to 70) some more times, but no more lag. At this point I wouldn't have been surprised if the Drive Battery Cooling Fan turned on again, and it did...but not until after about ten minutes of driving slow on city streets.

    I'm nervous this might be the first sign of drive battery issues. The Green Bars still go to the top.

    Fortunately I wasn't planning to drive it again until it's appointment in a week for 100K service at Art's here in Berkeley, California.
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,796
    48,995
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    yeah, it could be borderline, since you don't have any codes. art will sort you out.

    maybe the fan is clogged
     
  3. coyote2

    coyote2 Member

    Joined:
    Jun 29, 2004
    123
    29
    0
    Vehicle:
    2005 Prius
    Model:
    Two
    Thanks very much for your reply, bisco! (I always forget about codes; I gotta get me one of those code reading thingies.)

    The fan being clogged is a nice thought, I'm gonna let that relax me until it's sorted!
     
    bisco likes this.
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,796
    48,995
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    no codes unless you have trouble lights on the dash
     
  5. coyote2

    coyote2 Member

    Joined:
    Jun 29, 2004
    123
    29
    0
    Vehicle:
    2005 Prius
    Model:
    Two
    Aaaah, I see. No trouble lights.
     
  6. coyote2

    coyote2 Member

    Joined:
    Jun 29, 2004
    123
    29
    0
    Vehicle:
    2005 Prius
    Model:
    Two
    Art's thinks it is the first sign of drive battery death.

    I was about to sell it when the pandemic started, and don't drive enough to merit a hybrid...but given the car shortage and the shape it's in (I had them do an inspection), when it does die I'm gonna drop the $2.6K on having them replace the battery.

    We didn't bother to clean the battery fan. The timing of the anomalous fan activity doesn't really suggest it, and I never had a pet in the car or drove an inch in dusty conditions when the windows weren't closed.

    If it weren't for my carpal tunnel, I'd probably clean the fan anyway just for fun.
     
  7. Wrecit

    Wrecit Active Member

    Joined:
    Jul 12, 2020
    165
    106
    0
    Location:
    Pittsburgh
    Vehicle:
    2001 Prius
    Model:
    I
    I missed your year but would suggest if nothing else find a mechanically inclined kid that can follow directions and pull the fan to clean it. You might be surprised how dirty it is. Pulled the fan on my 06 and it had maybe 1/4 inch space between the black fan blades. Imagine my surprise after I sprayed the fan down with some 409 and discovered the fan was white and the space was actually 3/8 of an inch or so lol
     
  8. nancytheprius

    nancytheprius Active Member

    Joined:
    Oct 25, 2020
    348
    151
    0
    Location:
    iowa
    Vehicle:
    2006 Prius
    Model:
    II
    my cooling fan was filthy! no pets and windows always up too so i wouldn’t assume it’s clean View attachment 217430
     
  9. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
    5,286
    4,226
    0
    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    A new OEM costs around 1800 with tax, plus the dealership refundable 'core charge'. Art's installation sounds a bit pricey, even if worth it.

    When the time comes, reach out and I can do the install for less or little/nothing, which would include cleaning the HV battery fan.

    Besides going with dealer OEM battery, there are currently a couple of NEW aftermarket options as well :

    NewPriusBatteries.com | Home (known product from a PC member, and in use for years now)

    https://projectlithium.com/ (fairly new technology, with no reported issues thus far)
     
  10. Wrecit

    Wrecit Active Member

    Joined:
    Jul 12, 2020
    165
    106
    0
    Location:
    Pittsburgh
    Vehicle:
    2001 Prius
    Model:
    I
    SFO depending on time frame neither are an option if it's second gen. Both are out of stock accepting pre order but I believe I read somewhere on Prius chat November is next shipment and already sold out. If I won the lottery I would gladly loan either company money to buy enough stock to keep these on the shelf though ..... Come on lucky numbers lol