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Start Battery Replacement

Discussion in 'Gen 2 Prius Main Forum' started by patcoghm, Oct 6, 2015.

  1. patcoghm

    patcoghm Junior Member

    Joined:
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    This is for information purposes about my recent Start battery going bad.

    A weak start battery appears to have caused brake warning lights, while just driving along the brake lights would come on and when the brake was depressed, they appeared weak and needed more pressure then normal, and then the tires would squeal at the last moment and make skid marks from 2 tires only on the road surface. Did this randomly for a year, until the car would not start while on a long driving vacation, replace the start battery (Little Battery) and the brake problem and warning lights has settled down to normal. Guess the voltage was on the verge of not enough and momentarily dropping out the voltage which shut the braking system down into manual emergency braking type system and the light would come on.

    The battery was almost 8 years old when these braking warning lights would appear, and failed after another year of occasional brake light problems. I always solved the problem by pulling over and turning the system off, then restarting and everything returned to normal. The Brake light come on about 5 or 6 times during the last year and Toyota could not find the problem as it returned to normal when they started the car in the shop.

    For your information, when the battery failed I was in Montana, 50 miles from the nearest Toyota dealer.
    I Jump started the car using the instruction in the manual. Needed to be on the charge battery 5 minutes before attempting to start. (Better read the book but that was my memory on what we did.) It started and the engine ran and never paused or stopped as it normally does. I Had no real power and pushing on the gas pedal increased RPMs slowly, and milked it on the main highway up to 55 MPH @ 4000+ rpms by pulsing or pushing the gas pedal. After stopping at a few signal lights, it again required the same slow pulsing of the gas pedal until it attained 55 MPH speed. The dealer replaced the battery after 9 years and said I got my money's worth from that battery.

    Finished the trip and all appears normal, except a new noise just appeared, which I mention in another post.
     
    bisco likes this.
  2. bisco

    bisco cookie crumbler

    Joined:
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    Vehicle:
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    Plug-in Base
    thanks for the warning. spend more quality time here, and avoid these problems before they happen!(y)
     
  3. kenoarto

    kenoarto Senior Member

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    Location:
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    II
    Let's see, the battery is designed to last 5 years. Several have posted 6 year lifetimes. Your's lasted 7. perhaps you should consider replacing at 5 years, before everything goes to hell again?