What did you do? What old parts did you use? How did you set it up for a 10 second delay? I can wire a button in there, but I would really like to spend some extra time and setup the bypass to delay about 10 seconds. The pioneer stereo I am uses boots up each time and a 2 or 3 second delay won't work. It needs a few more seconds.
I used a relay out of an old TV or stereo system board, a transistor or two, a handful of resistors and a capacitor to to delay the start time of the relay; i bread boarded it to get it dialed in. Basically the transistor doesn’t conduct while the capacitor charges up first boot up each time, then once the cap reaches a target voltage it switches on the relay. It isn’t precision timing, but haven’t had any problems out of it. It’s powered by the remote output so just allows the relay to wait about 10 seconds after the head unit turns on before its contacts close, pretty crude really. That said, my circuit wouldn’t work the same for all relays and I didn’t do a schematic for it as I tested on a breadboard until I got it dialed in. I use to do electronics repair so already had tons of old / spare parts laying around to play with, hence it cost me nothing.
That said, you could buy a bypass for what the parts cost to build it if you had to buy parts. The bypass kits are fairly cheap and guaranteed to work, I only built one since I had parts and I’m cheap like that. If you were to build one, a 555 timer IC would be the way to go, and you can find videos on / schematic to delay the start of a relay with it.
The board posted above might work okay as well.
The legit bypass kits are likely much smaller though and easier to install / mount. I honestly wouldn’t recommend anyone waste the time building one unless you have the parts and have a rough idea how to do it already.
I wonder if the OP’s bypass he ordered worked out okay.