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remote key/door opener suddenly stopped working

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by LM120253, Dec 15, 2017.

  1. LM120253

    LM120253 New Member

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    2007 Prius
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    I had some minor front end repair work on my 2007 Toyota Prius. When I picked it up for the body shop, the FOB would unlock the doors but not remote start so I inserted the FOB into it's slot and was able to start the car. I thought maybe the battery was going dead so I replace the battery in the FOB when I got home and checked to make sure the car would still lock/unlock. The next morning my wife couldn't unlock the car with the FOB and told me that evening. So I thought the FOB wasn't working so the next day I went to my local dealership and bought a new FOB. They were initially able to program it but when they gave me the new FOB, I was able to unlock and lock it remotely but wasn't able to start it remotely, I had to insert the FOB into it's slot and was able to start the car so I went back in to the parts department and got the guy who had programmed the remote and when we went back out to the car, we couldn't unlock/lock the doors or start the car remotely so he had the technical re-program(?) the computer and still wasn't able to use either the new or old FOB and said they would have to charge $120 diagnostic fee to diagnose the problem.

    In reading posts on this website, I saw that there are four parts in the SKS system:
    (1)- fobs
    (2)- sensors
    (3)- KCM (keyless control module)
    (4)- Coil Antenna

    It sounds like my problem is more than likely in the KCM or Coil Antenna.

    Where can I find pricing on those items?

    And how can I determine which unit might need replacement?

    Thanks,
    Leon.
     
  2. bisco

    bisco cookie crumbler

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    has anyone checked the 12v health?
     
  3. LM120253

    LM120253 New Member

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    I replaced the 12v battery last year and hadn't experienced any problems with the keyless until now.
     
  4. bisco

    bisco cookie crumbler

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    cheap and easy, worth checking, even at one year old. after that, it gets more difficult.
     
  5. DD1

    DD1 Junior Member

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  6. exstudent

    exstudent Senior Member

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    FYI, Gen2 Prius (2004-2009) CAN NOT BE STARTED REMOTELY; such an option was not made available from Toyota. Very definition of remote start means, pressing a button on key FOB, to have the engine turn on and start running; this is a desired feature for people in cold/snow region to get the engine warmed-up, or people in hot climates to have the AC started to help cool the car before entering (requires AC to be left on previously).

    You are confusing "remote start" with Keyless Starting [not having to insert a key into the ignition (FOB slot for the Prius) to start the car].


    1) 12V battery health? Body shop could have unintentionally ran it down.

    2) Is the SKS system turned "ON"?
    upload_2018-10-9_23-58-47.png

    If SKS is ON and 12V battery is healthy, then IMO (In My Opinion), everything points to the body shop and a possible cover-up.
    • SKS system was working correctly prior to you dropping the car off for body shop work to be performed.
    • Body shop accidently destroyed your SKS fob, and replaced it with a used SKS fob (silver Toytoa logo on back of fob) or possibly a non-SKS fob (toyota logo is black).
    • RFID chip was transfered over into the used SKS fob.
    • SKS fob battery has been eliminated as a possible cause; assumes the new fob battery is correct battery and a strong 3V.
    • Dealer attempted to program a new SKS fob via 'chicken dance,' to no avail, since there was no correct working SKS fob present.
    • Dealer 2nd attempt to "reprogram" SKS fob, likely screwed things up further.
    • Your best bet is for the dealer to do a Rest and Reseed. Call dealers and price shop this service; its expensive (a few hundred). Used SKS fobs are discouraged from being attempted to be applied to the non-original SKS Prius, b/c of labor costs; cheaper/faster to buy new virgin SKS Fob for programming and incur less labor time charge.
    • It is also possible that the SKS fob circuit board could experienced a freak failure; thus the problems.
    • It is also possible that the SKS ECU's experienced a freak failure too; very rare, as I only recall reading about this twice.

    Read this for further understand of SKS: SKS Fobs only work wirelessly | PriusChat
     
    DD1 likes this.