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" B" Mode?

Discussion in 'Gen 3 Prius Technical Discussion' started by alfon, Jul 16, 2009.

  1. alfon

    alfon Senior Member

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    Has it been confirmed that when in B Mode going down hill and used for breaking the engines turns?

    Alfon
     
  2. HTMLSpinnr

    HTMLSpinnr Super Moderator
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    At high enough speeds, yes. If the battery is "full", the engine will turn "more" (higher RPM). I've also seen low speed B mode operation act just in a charging capacity w/o spinning the engine.
     
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  3. Old Bald Guy

    Old Bald Guy Old Bald Guy

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    B mode is like a Jake Brake. When you are going down a long hill, it turns your gas engine into a big air compressor and slows you down without burning up your brakes.

    Using Drive going downgrade is OK until the computer says your battery is full enough ... then you loose regenerative braking because there is nowhere for the excess electricity to go. So you ride your brakes OR use your Jake Brake B mode.
     
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  4. RFBrown

    RFBrown New Member

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    This is one of the better explanations of a jake brake. air compressor simile is a good one.