It's summer, check your radiator fans before hot weather driving

Discussion in 'Generation 1 Prius Discussion' started by 3prongpaul, Jun 10, 2013.

  1. 3prongpaul

    3prongpaul Hybrid Shop Owner, worked on 100's of Prius's

    Joined:
    Jul 18, 2010
    954
    724
    1
    Location:
    Boulder Hybids, Boulder, CO
    Vehicle:
    2006 Prius
    Model:
    N/A
    This weekend I learned the hard way that Gen1's do not throw an error code if the radiator cooling fans don't work....until it's kind of late.

    I tried to go over independence pass in Colorado in 85 degrees weather with AC cranked. 1/2 way up the 12,000 ft mountain pass RED coolant warning light came on. Pulled over, hooked up Techstream ICE coolant was 260 degrees and boiling through the overflow tank. Not good.

    Waited for car to cool down, limped downhill to the nearest town, let car cool for over an hour then topped up radiator with distilled water (no place selling coolant on Sunday). I was able to drive 200+ miles in the cooler evening at freeway speed on the (less steep) interstate.

    However, going uphill mountain roads or stop and go city traffic you can overheat the car if the your fans don't work.

    Easy to test your fans, turn on car on hot day then crank on AC, look at fans, they should first spin slow then fast (noisier) when engine gets hot. Both fans on my car had died, yet no codes until engine was boiling, no blown fuses.

    Checked fuses, relays, all good. Hooked 12V direct to fan connectors, nothing.
    Replaced both fans today. Now working properly again. Hopefully no permanent damage to ICE.

    BTW, fan carrier shroud is held on by 2 x 10mm bolts. Remove bolts near top, pull shroud up about 1" to unhook from lower mounts then move whole unit down to remove from car. Car should be on rampstands or lift. Hardest part is getting the electrical connectors undone, you may have to remove the drivers side big radiator hose to access them.

    Lastly, this if the first Gen1 I've seen with bad fans. Car has 270k miles on it.
     
    bwilson4web likes this.
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,200
    6,485
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Good point.

    In addition if the car had previously been in a front-end accident, make sure the fans are spinning in the right direction (air flow towards engine). Several cases reported of (2G) fans installed so they are blowing air out of the radiator, which means the engine will overheat at freeway speeds.
     
  3. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    25,205
    16,451
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Good info, Paul, thanks! I trust that means the assembly can come out with no need to open any refrigerant lines? (I seem to remember seeing that as a step when I first obtained the manual and was skimming through it, and thinking ... you gotta be kidding...).

    -Chap