How do I ground the valet switch

Question

Im installing on a 2015 Mazda 3 and I’m seeing that the valet switch can be used in place of the hood pin. I see it just needs to be grounded? Does this mean I just need to splice one wire from the switch to the blue wire on the harness and then the other wire to another ground wire or Somewhere that’s metal? Also, if I install this and decide I’d like to change a setting on it, can I just unplug it from the car and then hook it up and change the setting and plug it back in? Or will I need to reprogram it with my keys and everything all over again? Would there also happen to be a way to control the front and rear defrosters with an added mobile remote start app? Sorry for all the questions!

Answer 1

see image below.