Odd smart entry smart start problem (2008 Prius)

Discussion in 'Gen II Prius Care, Maintenance and Troubleshooting' started by brianw, Sep 15, 2010.

  1. brianw

    brianw New Member

    Joined:
    Apr 24, 2009
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    Texas
    Vehicle:
    2008 Prius
    Model:
    N/A
    Alright, so I take the car in for some work and get it back from the shop and the smart start and smart entry didn't work afterward, while the fob worked if I pushed the buttons to unlock/lock the door. Been there done that I figured. Surely they had pressed the key button again and disabled the SKS. That was not the case though. With the button in or out it made no difference, the smart start and entry are not working. I've heard it suggested that if the battery goes out maybe it would allow you to use the door lock and unlock button after the battery was too weak to unlock or start the car remotely. I'm not buying that I can unlock the doors with the button with a weak battery but can't start the car with the fab in the car. Any ideas?

    I can replace the batteries and maybe both batteries got weak at the same time but since the change occured when the car was at the shop and likely had the battery disconnected I am thinking that is too much of a coincidence and that had something to do with it.
     
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    My idea is that you should just replace the fob battery (CR2032) and then see if your car still has a problem.
     
  3. brianw

    brianw New Member

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    Texas
    Vehicle:
    2008 Prius
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    I'll do that. I read that if you push any button on the fob and the red light blinks that it has enough charge that all functions should work properly, but maybe that is not the case.

    I did a search on this site and someone suggested to someone with (seemingly) the same problem replaced the batteries to his fobs with no luck, then spent a few hundred dollars on new fobs with no luck. Someone suggested his 12 volt battery might need replacement. My 12 volt battery has not been replaced but surely that powers more than the SKS system and a bad battery would cause other problems besides just this SKS problem.
     
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
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    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Yes, I'm suggesting that you take the action with the least $ cost first. It would be premature to say that the 12V battery has a problem.