1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Unique Key Fob Reprogramming Circumstances

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Enoch Heckman, Sep 22, 2019.

  1. Enoch Heckman

    Enoch Heckman Junior Member

    Joined:
    Sep 22, 2019
    1
    0
    0
    Location:
    Fair Oaks, CA, USA
    Vehicle:
    2004 Prius
    Model:
    Five
    Hey so all the help forums and videos don’t seem to address my circumstances regarding reprogramming the key fob.

    1. I have only 1 key fob
    2. It stopped working when my battery died/since I replaced my 12V
    3. Starts the car when plugged in, but doesn’t remotely unlock/lock
    4. Old fob (current) case is damaged
    5. I have a new fob case
    6. When the chip and battery are placed in the new fob case it doesn’t work to start the car
    7. I put everything back and we’re back to square one. The reset protocols are null without a new chip involved as far as I can tell, but up to that point in each process when it calls for a new battery, everything works.
    How do I reprogram my current fob without having to buy a new key entirely? I want to replace the case or at least to get the smart features (lock/unlock) working. Right now I am using the physical key to unlock my car.

    Thanks in advance! I know somebody knows how to solve this one!
     
  2. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,487
    3,763
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    Ok, first things, there are two internal components you need to transfer over from the old case to the new one.
    1. The printed circuit board (PCB); and
    2. the RFID chip. Attached is a photo of where it is located and what it looks like.
    Very many people do not know to transfer the RFID chip and is the single most common mistake.
    Prius Key Fob RFID Chip 2.png Prius Key Fob RFID Chip.png

    While you have the PCB out, give it a good clean (especially the switches) with PCB cleaner spray and a firm brush.. Check, also, the switches work. When you tae done all this, check if your fob now works. If not, read on.

    Does your car have SKS or no?

    Once you have the key in the new case, you may need to visit a dealer or a good certified auto lock smith with experience and equipment to add the key back to the car.

    Moral of the story do not rely on only one key fob. Once you get your existing one working, buy a brand new one and add it to your car using the "Chicken Dance" so you are not in this situation again.
     
    Skibob likes this.
  3. mlsimmons

    mlsimmons Junior Member

    Joined:
    Dec 19, 2019
    23
    2
    0
    Location:
    Everett, Wa
    Vehicle:
    2005 Prius
    Model:
    N/A
    I recently purchased a high mileage gen2 from the original owner- it has the smart key system - it came with one fully functional key fob and one with a "dead" battery , both with the silver logo - the one with the dead battery would still start the car if it was plugged into dashboard but neither the buttons nor the SKS functioned - so I replaced the battery but that didn't help - so I did the chicken dance using the good fob as the "original" key but that didn't work either - unfortunately in doing so, I lost the functionality of the push buttons on the good fob even though the SKS system is still working with it. Anything that I can do to restore the push button functionality on the good fob? I also purchased a new key from a Toyota dealer so that I would have 2 good working fobs as this site recommends. I am reluctant to program it untill I restore the full functionality of the good key - any help/advice would be much appreciated
     
  4. mlsimmons

    mlsimmons Junior Member

    Joined:
    Dec 19, 2019
    23
    2
    0
    Location:
    Everett, Wa
    Vehicle:
    2005 Prius
    Model:
    N/A
    FYI - I did some more research on this site and found a similar issue that was solved by un-sticking one of the buttons on the fob - in particular the panic one - I rechecked the good fob and found that my panic button also was stuck - I freed it up and now the fob is back working
     
  5. RobH

    RobH Senior Member

    Joined:
    Sep 18, 2006
    2,369
    978
    70
    Location:
    Sunnyvale, California
    Vehicle:
    2006 Prius
    Replace the keyfob case. New one should last another 15 years...

    Be sure to transfer the transponder chip as well as the separate circuit board.