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Adding amplifier without deep discharge battery

Discussion in 'Gen 2 Prius Accessories & Modifications' started by Bam36, Sep 19, 2011.

  1. Bam36

    Bam36 New Member

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    I would like to first apologise if this is a copycat thread of any other I'm new and also very lazy. To get on with it I was planning on having a 320 Watt RMS Rockford Fosgate Amplifier installed to my '04 Prius to run a 250 Watt RMS Rockford fosgate subwoofer and whenever I have asked a question about it anywhere else I always get an answer that has absolutely nothing to do with the question. Anyway, I'm planning on having it ran through the AUX battery as I've read you're supposed to but I've seen a lot of posts warning that I should upgrade to the Deep discharge battery that would cost me $200 and whatever install would be when I find a mechanic gutsy enough to install it (I'm not very mechanically savy). I don't even know how to access the 12V battery or even which side of the car it's on for that matter. If you are still reading all of my babbling you're probably just wanting me to get to the point already, main questions being::focus:
    1) Do I really urgently need the deep discharge battery or should I be fine without it?
    2) Would the amp be pulling too much power? Should I go for somethign weaker? Maxes at 500 Watts (tried to keep the wattage as low as I could while retaining high quality brand and tremendous bass, I'm a bass junkie had 2 12's in my last car).
    P.S. I have the JBL system and it met my bass need for a while until I burnt a voice coil on the the front passenger side woofer and toned it all down. Dealership wanted $130 just for a new woofer exlcuding install costs, I'm just diconnecting it and getting a subwoofer for the back.
     
  2. jdenenberg

    jdenenberg EE Professor

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    If you only run the amp while your Prius is in "Ready" mode all will be fine. If you have a good tech install a relay that requires "Ready" mode to run the amp, that will protect the little 12v battery from being drained. Your amp pulls enough current to drain the 12v battery in about an hour (sooner if it is not fully charged or nearing its end of life). One or two full discharges and you will need a new 12v battery.

    JeffD

    ps. You should learn how to safely jump start your Prius. First - NEVER connect a jumper battery backwards as it could be quite expensive to recover from the damage. Second - there are two places to connect jumper cables.

    1. At the 12v battery which is below the carpet and spare tire cover near the passenger rear wheel well.
    2. At the "Jump point" under the hood. You open the hood, lift off the fuse box cover (near the firewall on the right facing the car), and open the little red cover over the Positive jump terminal. You connect the RED (positive) cable to that terminal and then the BLACK (negative) to any convenient bare metal part of the car body.
    NEVER use your Prius to jump another car as the high current drain to do this can again cause damage.
     
  3. FrogmanDave

    FrogmanDave New Member

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    I see what you mean by off topic comments to your questions. I'm not sure where all of that 'jumping another car' came from.

    I am running a 600 watt mono Kenwood amp and a 260 watt 4 channel amp directly off the 12 volt battery in the back of the car. My system runs just fine. There is no light fading when the bass hits or any of that. You will be fine.
     
  4. Bam36

    Bam36 New Member

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    Thanks so much for the advice that is definately good news to hear. I don't plan on using it without the car in ready mode and even if I do it's only to program my GPS for a trip the next day for about 5-10minutes at the worst plus I'm getting a power knob with the amp to turn it down in such cases. I was also wondering about where to run the remote wire to, I know the install techs usually do it to the ignition but for obvious reasons that won't work this time around and I'm probably bringing them the first prius they've ever done? Also where EXACTLY is the 12V battery located because I'll probably need to tell them where to look so they don't completely gut my car trying to find it? Last question is; is there a way to avoid losing all my programing in the car when they install it.
     
  5. PhazonPhobe

    PhazonPhobe His name is Sora

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  6. jdenenberg

    jdenenberg EE Professor

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    As I noted above, just lift up the cover to see the spare tire and look to the right. The little 12v battery is snugly fit behind the passenger rear wheel well
    If you connect a jumper battery at the jump point to maintain 12v power while the battery is disconnected, you will not lose any settings. Make sure to not let the positive cable touch anything or you will see sparks. Of course, your Prius should be off while doing this work.

    JeffD
     
  7. F8L

    F8L Protecting Habitat & AG Lands

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    Jdenenberg basically covered it.

    The reason he was trying to educate on jump starting is because high wattage stereo systems can drain the battery so low that it requires a jump start. It has happened to me a few times on the oem battery. The highest wattage I've heard of being ran in a Prius was 1900 watts RMS, not peak power which Phazon mentioned he is running.
     
  8. Doc Willie

    Doc Willie Shuttlecraft Commander

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    I drained the battery several times, forgetting to leave the car on while running the sound system (JL Audio, 800 watts) at a car show. I carry a jumpstart battery with me all the time. My original battery lasted about three years, and I replaced it with an Optima. Have only drained that dead once.

    The jumpstart battery has come in handy several times to help other people jump start their cars (including a Corvette at a car show! I suppressed my snickers till I left.).
     
  9. FrogmanDave

    FrogmanDave New Member

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    Good point F8L. My apologies to the OP and to Jdenenberg. I stand corrected sir!
     
  10. F8L

    F8L Protecting Habitat & AG Lands

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    No worries. :)

    Now I need to go fix my spelling errors. Posting with a cell phone sucks.
     
  11. Bam36

    Bam36 New Member

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    So glad I asked I definately feel much better about everything, thanks to all of you.