Programming a New Non-SKS Key for a 2007 SKS Prius

The black and silver keyfobs have completely different circuit boards in them, and they communicate with different protocols. They do share the same transponder chip, which is why you can use either type plugged into the dash.

Both SKS and non-SKS vehicles have the "Body" computer, which is documented as handling the non-SKS keyfob button signals. The SKS vehicles have an additional ECU that handles communications with the SKS keyfob for the button and proximity functions.

Now, the interesting question is whether or not a SKS vehicle could recognize a non-SKS keyfob. One of the setup parameters for the Techstream scantool is which type of key system is in use. If a mechanic selected the non-Smart key system option, even though the car had it, what would happen? First guess is that it wouldn't work. Next guess is that it could really mess up the existing smart key registrations. But the real answer is that nobody has reported what happens. And I doubt that you could convince anyone in a Toyota dealership to even try it.

 

I have 4 SKS keyfobs plus a non-SKS keyfob for my SKS car. In order to program the 2 used SKS keyfobs, it was necessary to do a "Smart Code Reset" with a Techstream scantool. A reset was required for each used keyfob. Additionally, the transponder in the non-SKS keyfob was registered, but the buttons on that keyfob are useless. Actually, I replaced the transponder in an ordinary key with the one from the keyfob. So I have an ordinary transponder key that gets me in the door with the metal blade, and works to start the car when I put it handle-first into the keyslot.

One use for the non-SKS keyfob case is as a replacement for a worn-out SKS keyfob case. A SKS keyfob with a damaged button can be fixed by transfering the circuit board and transponder to a non-SKS case. Anyway, hang on to a non-functioning keyfob because it may be useful for the parts sometime in the future.

The price for programming keyfobs at Luscious Garage | Blog | Full Service Prius Key Programming is listed as $30 for a new keyfob, $100 for a used one. That's a lot better than anything I've seen at dealers.

 

Rob,

Could you describe exactly what you mean by putting the transponder in "an ordinary key" that works in the keyslot? Does the handle fit in the keyslot well, or do you have to hold it there while you start?

By the way, what does your "ordinary key" look like? Do you have pictures, an item number, or a link to somewhere that the same "ordinary key" could be purchased? I'm sure there are many of us who would like the function of your modified key, but don't want to have to resort to using separate keys for the door and ignition or some sort of duct tape and crazy glue home-made device that looks like it belongs in an episode of MacGyver.

 

Rob,

Did you use a regular Toyota transponder key? I saw some on ebay for about $10 listed as "Toyota Transponder Key - 4C Chip". Would it be correct to assume that you just opened up an old non-SKS keyfob and put its transponder inside the "ordinary transponder key" to replace its original chip, then programmed it to start the car with the instructions posted elsewhere on PriusChat?

If this is what you did, then it is exactly what I had in mind for my own emergency spare key!

 

You got it. I tried a variety of transponder keys, including a Gen1 Prius key, a Camry (4C?) key, and a 4D-67 transponder that I ordered from China. No luck. Then I got a black logo keyfob cheap ($20?), registered it in the ordinary way (key in dash only). Next I broke open the keyfob and took out the transponder chip.

The transponder chip is all you really need for the ignition. At one point I just taped it to a pencil, pressed it into the keyslot, and it all worked just like it was the keyfob. The only hitch is that the keyslot normally locks the keyfob into it, and you have to release the keyslot by pressing it after you turn the car off.

So I butchered one of the transponder keys that didn't work, and put the transponder from the keyfob in the plastic holder that was left. I destroyed the rubber molding figuring out where the transponder was. I could probably do a better job with another key blank, but it's adequate for my purposes.

Note that the transponder doesn't work if it's just taped to a metal key head. Apparently it has to be away from too much metal. The sensor in the keyslot is on the bottom of the slot at the back.

Note also that this applies to Gen2 only. The Gen3 doesn't have a transponder in the keyfob. The Gen3 seems to use the ordinary signaling, with enough power picked up inductively from the Power button. I've tried just a bare Gen3 circuit board (removed from the case & battery removed), and it works next to the Power button.