Two queries: 12 v battery and tires

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by chutneypopcorn, Dec 13, 2007.

  1. chutneypopcorn

    chutneypopcorn New Member

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    Hi Prius aficionados, I have two questions which have likely been answered before, but humor me please, or feel free to direct me to the relevant threads:
    1. I have a 2007 Touring, 5500 miles, with all the bells and whistles-worked great until a week ago when I found it dead as a doornail in the parking garage! My panic-stricken reactions and what ensued until I jumped the 12 v battery are besides the point; the point being-why did the battery drain when I had driven the car from the airport 4 days earlier (about 22 miles) and there wasn't a light left on or a door left open. The SKS was on, as it always is. The headlights were turned off. I drive the vehicle once, oh every 2 weeks, about 80 miles. The tech at SF Toyota checked it out today, gave it a thumbs up, and said i needed to drive it every week at least once. He didn't have any other insight, just a very large friendly smile and a request to fill out an email survey about his service. Any pointers? I am waiting for the other shoe to drop...I will be heartbroken if there was another shoe!

    2. I replaced the OEM tires with Bridgestone Potenza RE 960 AS Pole Position, 205/55R-19 91W B, because they were recommended (by...some research I did a while ago, I think) Today the pressures were "30 all around" per the tech who obliged to check it with his basic tire gauge. Recommended pressures are 35/33 he said, but it doesn't matter. Please come back another time, :D, and maybe we will, :D, change it or something or another...if the ride is...not smooth, :D. My concern is mileage and safety. Wondering if I should bring up the psi to 35/33? Are optimal pressures intrinsic to the tire or dependent on the vehicle the tires serve?

    As always I appreciate your attention. You guys are amazingly resourceful and well-informed.

    Thanks!

    Neel
     
    #1 chutneypopcorn, Dec 13, 2007
  2. efusco

    efusco Moderator Emeritus
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    1) Sans a crystal ball it'll be hard to know for sure. One common cause is the rear hatch, if not tightly closed, can drain the battery...it can look closed, but that little rear hatch light stays lit and causes a drain.

    2) YES boost that pressure. 30psi is probably both unsafe and terrible for your fuel economy not to mention your tires will wear faster and your handling will suffer. You didn't say what the sidewall PSI rating is on those tires, but most of us run in the 42/40 range...some of us even higher.
     
    #2 efusco, Dec 13, 2007
  3. chutneypopcorn

    chutneypopcorn New Member

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    Thanks efusco!

    Appreciate the prompt response, will check what the recommended pressures for these tires is...tried to do that online last night, couldn't find the numbers.
     
    #3 chutneypopcorn, Dec 13, 2007
  4. N3FOL

    N3FOL Member

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    Dead Batt

    I agree, that rear hatch if not closed properly may drain the batt due to a small lamp that remains on all the time. However, I still need to find out whether my Prius will give me a warning beep as I lock all doors with the hatch not closed all the way. ( I think it will :confused:)

    As for the tire pressure, 30 psi is a bit too low. I don't even go with 30 psi on my motorcycle tires. I found out with about 1400 miles so far is that 38 in the rear and 40 in front is good. My mpg has been going up steadily...from 44 mpg now I am into 47.87 mpg in December. :D
     
    #4 N3FOL, Dec 13, 2007
  5. jayman

    jayman Senior Member

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    The rear hatch is tricky and easy to improperly close. Sometimes when I use the lock button, the car will beep at me, sometimes it won't. I've just got into the habit of giving the hatch a firm slam shut

    I was having trouble the first winter with my Prius. The constant Max Heat and electric defrost operation severely drained my 12 vdc battery.

    I had just picked up some older model VDC Electronics Battery Minder units at auction, and hooked one up to my Prius. A search of this forum should find the posts I have made in regards to the battery tender

    Now that I use the VDC whenever the car is parked inside, the battery seems fine. When I power up, the auto headlights hardly even flicker
     
    #5 jayman, Dec 13, 2007
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