Hello all!

2009 fx4 - passenger seat with no memory. Kind of random question, but I am trying to do a fun project in the truck, where I plan to control the passenger seat via an Arduino micro controller.

I'd like to be able to let the passenger control their seat on their own via the switches as normal, but I would also like to be able to control the seat via the microcontroller as well. My plan for doing this was to splice wires into the seat harness from the Arduino, and then just send a 12V signal to each wire for the various seat functions as it comes right out of the seat switch, as if the switch was closed and sending power. I tried to test my theory today by manually jumping the power wire from the harness going into the seat switch to a different pin on the same harness (truck side, not seat side) and got nothing. My thought is that nothing happened because I didn't have ground connected to anything and I need to jumper the ground to truck ground, while jumping power to a different pin in the truck side harness? Am I even close to believing i can do something like this? Is there an easier way? I plan to test this out again tonight, but before I do, want to get some other opinions or warnings if I might fry my ECU. The attached pic shows my test plan for tonight...


If this works, I would splice into the wires on the back side of the harness, send 12v into the specific wire I want to control when I want to move it, otherwise, the seat switch would do the rest.. back side of harness/where I will splice, below



​​​Thoughts?

Thanks in advance!
Greg