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Car thinks fob is in the ignition overnight, now won't start

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by barbie.gee, Nov 13, 2012.

  1. barbie.gee

    barbie.gee Junior Member

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    Last night when I parked my 2005 Prius in the garage and turned it off and pulled out the fob, I thought it was strange that I then got the "beep" signal when I opened the door to get out, but it didnt' really register for me what that might be. I closed the door, checked the others, and went in for the night.

    This morning, I went to start the car, and all the dash lights started blinking. Weird. So I attempted to turn the car Off and take the key out of the ignition, to try again. But the key wouldn't come out! A couple more tries and I got the key out, but the yellow check engine light on the dashboard is on, and the headlights were on. I turned them off. Now I think the starter battery is drained. I'm not sure if the Prius thinks it's ON or not.

    Earlier this summer, I replaced the original startup battery on my own, with an Exide battery, rated slightly more powerful. see: dead. just dead. battery? or?? | PriusChat

    Should I just call for a tow to a Toyota shop, or call for a jumpstart first, or what? I'm thinking maybe I should disconnect the battery, to "reboot" the car, but then I still have a battery with no juice... sigh.
     
  2. barbie.gee

    barbie.gee Junior Member

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    oh, I called my BF (50 miles away) and he said I should be able to disconnect the battery circuit somewhere other than having to open up the back of the car and disconnect from the battery itself. That way at least I'm not still draining the battery.
    Is it a fuse or breaker, and where is it???
     
  3. koolingit

    koolingit Member

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    I don't know how much experience you have working with tools and I mean no disrespect -- but since you installed the new Exide battery yourself, it might be worth your while to check all the connections to the battery. If you didn't tighten all the connections correctly, something may have worked lose.

    While you're at it, check the bolt that connects the ground cable to the body of the car.
     
  4. barbie.gee

    barbie.gee Junior Member

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    I'm going out to the garage now to see what's going on in the battery compartment... I cranked those connections down pretty tight, with a ratchet wrench, so I'd be surprised if the connections are loose, but you never know....
     
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Another way to disconnect the 12V battery is to open the main relay/fuse box near the inverter, find the dedicated positive jump start terminal hiding under the red cover, and use a 10 mm socket to remove the nut on the stud. Then pull up the wire attached to the stud.

    However, since you've already installed the 12V battery and know where the negative cable is, you might want to disconnect the battery back in the hatch area. I agree with the suggestion that 1) you should check the tightness of all connections and 2) use a battery charger to charge the 12V battery overnight, using a 4A charging rate.

    If you turn on the headlights and find they are dim, that is good proof the 12V battery needs a charge at minimum.
     
  6. barbie.gee

    barbie.gee Junior Member

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    Lights are dim.
    :-(
    the bigger question then, is why the battery discharged...
    back in a few, I'll take a photo if anything is awry.
     
  7. barbie.gee

    barbie.gee Junior Member

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    ARGGGH.
    I forgot that when the battery dies, the hatch door won't open, so I have to unlatch it from the inside...
    ffffffffoooooooey!
     
  8. John H

    John H Senior Member

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    Since this not the OEM battery, can she use a higher amperage charge rate? The Optima guy says 10A is ok for charging the YellowTop but this is an EXIDE.
     
  9. barbie.gee

    barbie.gee Junior Member

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    near the inverter ... dedicated positive jump start terminal.
    Must find it.

    I got into the hatch, into the 12v battery compartment, but can't unscrew the neg. from the body. It's cold in the garage and somehow I'm not as nimble as I was in July. The neg. wire is secure. Can't find my cheat sheets for how to remove the red positive terminal cover, and shouldn't touch it til the negative is disconnected, so back to the engine compartment... and back to doing a search to find that walk through I used. If I can get to the battery terminals, maybe I can get someone to lend me a charger, and see if I can restart the car to get it the 2 miles to the repair shop.
     
  10. ahmeow

    ahmeow Prius Lover

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    BTW, is the battery in the fob near expire (3V)? Change it every two yrs will be an insurance.
     
  11. barbie.gee

    barbie.gee Junior Member

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    When I get myself to the local auto parts store (walk, walk, walk), I'll pick up 2 new fob batteries, as well as a battery charger. What should I be looking for in a battery charger?
     
  12. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The battery charger should be for 12V automotive batteries and have the capability to charge at 10A as well as a lower current setting such as 4A or 2A. A fancier charger may have a different charging scheme for AGM batteries vs. traditional flooded lead acid.

    If you are charging the Toyota-supplied GS Yuasa AGM battery you will want to limit current to 4A. I don't know about the Exide battery that you have, look at the warning stickers to see if there are any current restrictions. If not then you can use the 10A setting.
     
  13. Britprius

    Britprius Senior Member

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    The Exide battery is ok up to 16 amp charge rate so 10amps will be fine. It is also an ultra deep cycle battery so no harm will have been done to it.
     
  14. Britprius

    Britprius Senior Member

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    In your first post at one point you say you noticed your headlamps were on. Were they left on from the night before?

    The reason I ask is because if the US version of the Prius is like the UK version if the headlights are on when you shut down the car the headlights go out but the side lights stay on discharging the 12 volt battery over night.

    The car warns you of this by beeping when you open the door.

    John (Britprius).
     
  15. barbie.gee

    barbie.gee Junior Member

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    This morning I went to check the battery charger, and it said my battery was now fully charged, 100%. I reconnected the battery, and put the fob in the ignition. Foot on brake, pressed Power ON. First time, all the dash lights came on, but I didn't get a "Ready", but I was able to power Off, removed the fob and repeated. This time, the car came on instantly. Feeling all lucky and proud, I got in the car, and instead of doing the *smart thing* and driving directly to a mechanic or the dealer, I was brazen enough to thumb my nose at common sense, and I drove to work, instead! 8 hours later, I was able to unlock the doors with the fob button, but DANG IT, the car didn't start. There was still the flashing security light on the dash. When I tried a few more times, even the light went away. So, my 12v battery is dead again! I was very careful when I parked the car this morning to be sure everything was turned off; radio, HVAC, dome lights, head lights, makeup mirrors... So either I have a defective battery, or there's something wrong with the electronics or a computer in the car that's eating the battery.
    I'll have to arrange for a tow and decide if I should trust a local mechanic or go a Toyota dealer and pay big bucks, tomorrow. In the meantime, any theories or ideas?
     
  16. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Yes, it is likely that either your battery is defective or your car has unusually high quiescent current when IG-OFF.

    I'll explain the general troubleshooting process so you can decide whether you can DIY. You need a digital multimeter to measure current flow.

    Make the Prius IG-OFF. Turn off the hatch and cabin ceiling light switches. Set the multimeter to read DC current and put it in series with the negative cable leading to the body sheet metal. Position the meter where you can see it when the doors and hatch are closed.

    Close the hatch and all doors and lock them. Keep the fob away from the car, at least 20 feet. After the Prius ECUs settle down, the quiescent current draw should be around 0.02 A.

    If much more, then the car has a problem with a stuck relay or an ECU.

    If the current draw is near 0.02A, then the 12V battery is probably bad.

    To find the quiescent current draw problem if one exists, you would then have to go through a process of pulling fuses one at a time to localize the problem. This requires you to have access to the electrical wiring diagram so you can see what fuses power which circuits.
     
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  17. barbie.gee

    barbie.gee Junior Member

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    Thanks for the info. That's probably more than I can manage on a DIY basis, though. I'm hoping to find a mechanic now who can do that for me! I can't believe that I don't find rave reviews for some independent Toyota mechanic anywhere in Chicago, and I fear going to a dealership will be all I've got available to me...
    Busy locating a mechanic near where the car is stranded this morning.
     
  18. barbie.gee

    barbie.gee Junior Member

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    I am in quite an interesting predicament now. The car is in a parking garage, and the garage has very low clearance, so I can't get a tow truck in! Can a Prius be PUSHED enough to get it free-rolling down the parking ramps? Or do all the wheels and steering lock up with no power?
     
  19. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The Prius cannot be moved out of P unless 12V power is available and the Prius made either IG-ON or READY. Maybe the tow truck driver has a portable jump start device so that the Prius can be jump started, in which case a tow will not be required.
     
  20. barbie.gee

    barbie.gee Junior Member

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    Will it keep running on a jump, no matter what? I don't want to get stuck half way between where it is and where I'm going...