Scion TC 2006 has resistive steering wheel remote controls.
It can be connected directly to CarPC JoyCon EX.

If SW1 and SW2 resistance value is duplicated, a resistor is needed to avoid duplication.

If you use CarPC JoyCon EX, you don’t need a resistor to avoid duplication.

7(SW1) -> DATA of CarPC JoyCon EX channel A

8(SW12 -> DATA of CarPC JoyCon EX channel B
6(SWG) -> GND of CarPC JoyCon EX