I can't find instructions to program a used key fob that I'd like to pair with my 2013 Prius. There is no dashboard slot and I am only finding instructions that require a dashboard slot. Thanks for any leads on this.
You need to first make the used key a virgin key. I don't know who does it anymore, some key places and some ebay people. Then you need to use a software (techstream or equivalent) to program the key
The instructions you've seen with a dash slot are for a Gen-2 Prius (2004 - 2009). Your 2013 is a Gen-3 which cannot be programmed without the use of Techstream dealer softerware.