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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    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 Sidewalk Supervisor

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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.
     
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  5. Siward

    Siward Member

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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 Sidewalk Supervisor

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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?
     
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  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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  9. Alfredo Farin

    Alfredo Farin New Member

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    when i press the button on the fob it illuminate a red light.No light however on the power button, no dashboard light and only the anti theft blinks.
     
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  10. bisco

    bisco cookie crumbler

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    i think you need to start with the 12 volt battery health test, and the tightness and cleanliness of the connections. especially negative to ground.
     
  11. Alfredo Farin

    Alfredo Farin New Member

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    the connection is tight and clean. Headlight turns on and blinkers and it honks too. I am just wondering why there is no power to dashboard and power button.
     
  12. Alfredo Farin

    Alfredo Farin New Member

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    is there a device i can use to bypass the immobiliser? or is there a button or combination ofbutton i can press to bypass the immo? I need help guys. The car is parked infront of my house for 2 weeks now
     
  13. AzWxGuy

    AzWxGuy Weather Guy

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    We don't know what the SOC (state of charge) of the recently purchased 12V battery is. A low SOC could cause what you are seeing as various ECU's fail to initialize. That could explain why some systems (lights, horn) work while other electronic controlled systems don't. My suspicion is turning toward wiring damage, maybe by rodents. Or something electrical was disconnected in the process of battery replacement and has not been reconnected.
     
  14. FuelMiser

    FuelMiser Active Member

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    This indicates the fob is powered normally
    I would focus on the "new" 12V battery. What should happen if the fob was dead would be "Key Not Detected" when you press the brake pedal and push the power button. Then another note pops up saying to hold the fob next to the power button. At this point, the green LED comes on in the power button and you are able to start--even with a dead fob.
     
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  15. mhagadorn

    mhagadorn Junior Member

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    I don’t think there is any way you can bypass the immobilizer. A failed body control module can cause similar symptoms. You might need to get a locksmith or someone with a good diagnostic tool.

    Do you have 2 smart keys / key fobs?

    Will it lock/unlock with the switch on the door?

    On both of my Toyotas, if I have a dead smart key battery, I have to hold the Toyota emblem on the back of the smart key directly on the start button on the dash. It can’t just be near it. It needs to be right on it.
     
  16. Alfredo Farin

    Alfredo Farin New Member

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    i bought the car last august in a second hand dealer, it comes with only 1 key. It does not unlock the switch to the door. I did what you said about getting the emblem directly on the start button dash, still doesnt do anything. No light on dashboard, no light on power button, only the blinking anti theft.
     
  17. Raytheeagle

    Raytheeagle Senior Member

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    Some questions:
    • Can you measure the voltage of each battery this morning before you try and do anything to your Prius?
    • You say you’ve had your Prius since last August (2017 or 2018). Did any event bring on this behavior?
    • Was the 12 volt in the Prius the original (do you still have it or look at the date code prior to removal)?
    • Any recent electronic additions to your Prius?
    • Any damage to the door mechanism?
    • Where did the AAA guy perform the jump (at the back of the car or under the hood)?
    • Did you watch him perform the jump or where he tried to connect it?
    • Have you checked for blown fuses, particularly under the hood?
    Good luck and keep us posted (y).
     
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  18. Alfredo Farin

    Alfredo Farin New Member

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    voltage is more than 12 v
    ive had is since august this year. It was already misbehaving like i go to work park it and then i wud need to jumpstart it so it will start. It happen like 3 times and everytime i just jumpstart it
    its not original but its farily new
    no recent electronic addition
    no damage to the door
    AAA performed it the front and at the back
    i did watch him and he tried multiple times
    i checked the fuses under the hood, everything is ok..

    im already out of creative ideas on how to fix this. I actually removed the after market alarm hoping that it would disable anti theft to no avail
     
  19. Raytheeagle

    Raytheeagle Senior Member

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    It sounds like this isn’t your first rodeo with jump starting your Prius :cool:.

    What I would do is get a multimeter and determine what the parasitic draw is and how much it is;).

    In the 9+ years I have owned our 2010 with 193 k miles on it (bought it brand new in August of 2009), I have never jump started it. To me that is a concern and something I would do first off as anything can happen when electricity is involved. The risk is higher when in a hybrid too.

    Have you checked the fusible link in the fuse box? If the AAA guy was struggling, he could have reversed the polarity causing the fusible link to blow. Hopefully that’s the only thing that got damaged cause if the reverse voltage got passed this, one of the next stops is the inverter and it could damage that:(.

    Good luck and keep us posted (y).
     
  20. Alfredo Farin

    Alfredo Farin New Member

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    Is the fusible link the big white rectangular shape device under the hood where all the fuses are? How do you remove those?
     
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