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New Hyb Batteries, New Hyb battery Fan. Doesn't seem right

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Haunsdoger, Feb 7, 2021.

  1. Haunsdoger

    Haunsdoger Junior Member

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    Location:
    Alamogordo, NM
    Vehicle:
    2005 Prius
    Model:
    N/A
    Taking the advice of this prius I replaced my hybrid batteries with new ones - not refers. It was a lengthy but fun experience and worked well. I was extra careful with sensors and air flow. However, the car doesn't seem to be charging with force. It charges up into the green. No codes thrown. So an investigation showed that the hyb battery fan wasn't turning - was on/off, on/off pulses so I replaced it and now it works well also. I travel about once a week up into the mountains (4000ft to 8000ft in 15 minutes.) The car uses every bit of energy from the battery and I have to pull over and "charge" the battery manually, then continue. I can say the process works (discharge/recharge) but just doesn't seem hefty enough. When new, it didn't go down into the red bars on the display. I fear the red bars cause that's when the old batteries threw the red triangle and I want to be gentle with the batteries to extend life. I am a very conservative driver. I have also replaced the regular battery, checked fluids and scanned my obd2 codes but it shows no codes.
    (200 mile trip up and back = 49.8mpg)
    Oh and the cruise control is now intermittent - works better when warm. but may be unrelated

    Is there something that can be done to get this car back in shape? Is there a way to test and verify that it is working as it used to? Do I send it off to the repair shop. (I am not a fan of dealership repair shops as they tend to find unrelated problems and not solve the ones that caused me to take it in). I am a electronic tech and have regularly repaired my own vehicles in the past.

    Thanks in advance for any advice or instruction
     
  2. JC91006

    JC91006 Senior Member

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    where did you get the new battery? You do not have to pull over to charge the battery, the car would run fine even with a bar remaining on the SOC display. The car's computer takes full control where you don't have to worry about it charging (especially for a new battery)
     
  3. sam spade 2

    sam spade 2 Senior Member

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    That first procedure is just false economy and it actually WASTES fuel instead of saving it.
    Just DRIVE IT.
    The onboard computers will "refill" the battery when you go back DOWN the hill.

    Chances are excellent that it is in fine shape......or at least reasonable shape.
    If the hybrid battery really was worn out, the whole car might just be getting OLD.
    Or your memory of how it used to work might not be 100% accurate.

    Don't create a problem where there really is NOT one.
     
  4. rjparker

    rjparker Tu Humilde Sirviente

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    Vehicle:
    2012 Prius v wagon
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    Three
    Are you saying you "have to pull over" and charge the battery because it faults and won't continue driving?

    The engine has enough power to get you up the mountain but the small amount of electric charge available at the time is just floating the battery rather than actively increasing its charge as it will do under relatively level driving.
     
  5. Haunsdoger

    Haunsdoger Junior Member

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    Location:
    Alamogordo, NM
    Vehicle:
    2005 Prius
    Model:
    N/A
    Well, thanks for setting me straight. I bought the batteries from new prius batteries as suggested by this forum. Nice looking batteries, worked well. It has not thrown any errors. I live in the desert with 100 miles without cell phone contact. Its not fun when you get VSC on a Sunday evening so I tend to worry about the car faulting on something I could have prevented. I guess I will drive the car and NOT look at that graph. HA. Thanks for your inputs.
     
  6. sam spade 2

    sam spade 2 Senior Member

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    Yep. That is a pretty important clarification.