I would like to add auto locking to my Prius. There is an established design that locks the door when both the start button and brakes are pressed (turning on the car). I found a single relay board on Amazon that appears to eliminate the needs for the second relay in the established design. I believe it does this because the trigger is separated from the relay power. Please let me know if my solution would work, and if not, what would I need to change. Thanks for any help.