2010 Prius Wont Recognize fob key, replaced 12 v battery and fob battery, anti theft blinking

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Alfredo Farin, Nov 4, 2018.

  1. Alfredo Farin

    Alfredo Farin New Member

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    Location:
    antioch, california
    Vehicle:
    2010 Prius
    Model:
    III
    I bought a 2010 prius with 172,244 miles last august. Working good but recently will lose charge on the battery especially on morning and will charge it with charger i bought from costco. One day last week went to work and when i was about to leave it wont start. I asked my friend to charge but it wont start. i ended up calling aaa who tried to boost it to no avail. Ended up getting the car towed to my house. I bought a new12 v battery and replace fob key battery but it wont start. i only see the anti theft blinking even when i get it it wont start. no light on power button. i put fob key near the power on, nothing. fob key wont open or close the car. There is headlight, light in the car is ok. when i press break. red light behind light up. No dahsboard light. I need help please..
     
  2. bisco

    bisco cookie crumbler

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    does the red fob light illuminate when you push a button?

    do you have any way to check for trouble codes?
     
  3. Georgina Rudkus

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    The lock symbol on the display only indicates that the keyless system is trying to detect if a smart key transmitter is present. It is not a security system.

    If you installed the wrong battery or a bad or weak battery into the key fob, no signal is produced by the key fob transmitter. I recall, you need the 3 volt battery. I do not immediately recall the number.

    There is a chip in the fob right under the chromed Toyota symbol on the fob. A fob with a dead battery can still work by holding the Toyota symbol to the start switch and pressing the clue start button. If this works, replace the battery in the fob and try again.
     
  4. Mendel Leisk

    Mendel Leisk Lapsed Cargo Cultist

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    Vehicle:
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    Model:
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    My 2010 shows a warning on the dash if low fob battery is detected. Maybe a Canadian model thing though, not sure.

    Test both batteries, for starters. With just a multimeter set to voltage, the fob battery for sure should be over 3.0 volts (IIRC I've gotten the warning on the dash even when it was right at 3.0), and the the 12 volt battery (test first thing in the morning) should be mininum 12.5, but brand new should be at least 12.6, though 12.7~12.8 is healthier.

    Fob battery should be CR 1632, at least according to my notes.
     
  5. Siward

    Siward Member

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    Vehicle:
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    I just replaced my keyfob battery last week, so I tested it with a multimeter. The old battery that kept giving me dash warnings was 3.03V (manufactured by Eunicide). The new fresh battery was 3.32V (which I ordered online from China).

    I would try starting the car with both keyfobs (if you have a second one) to rule out if it is a keyfob problem. The keyfob should be able to lock/unlock your car remotely if it has power and is working.
     
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  6. Mendel Leisk

    Mendel Leisk Lapsed Cargo Cultist

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    I order stuff thus too, but it tends to be things nigh impossible to find locally.

    Which sadly is more and more these days. For batteries I just walk over to the mall, pay through the nose. There's a rumor our mall is slated to be torn down soon, replaced by highrise condos. :(

    One more thing: if I get the fob battery warning on one, I replace them both, kinda like headlights I guess: if one's going, the other's likely not far behind.
     
  7. milkman44

    milkman44 Active Member

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    Is it possible, one of the battery jumps could have been polarity reversed if so there's a fuse or fused link that gets fried?
     
  8. JimN

    JimN Let the games begin!

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    USA models have the same warning. A fob with a weak battery will function for quite a while until it doesn't.

    The last time I bought fob batteries I could buy a full card (8?) on line for what one sells for in a retail store--after looking on line for a retail store with one in stock.
     
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