Hi Bill -
Thanks for responding. As far as getting discouraged, your post has done the opposite and energized me. It looks like the project is more realistic than I thought.
I believe you are correct in there only being a single bulb left and a single bulb right. I may have misspoke by saying input triggers. I’ve done a little more research, and I think the different triggers (or signals) are actually going to be based upon power status to the two turn signal wires (ignoring the marker light wire): both constant on (brakes), L constant/R pulsing (right turn), R constant/L pulsing (left turn), and both pulsing (hazard).
One of the questions I have is how to make the controller see the pulsing signal from the turn signal, vs. constant on from the brake signal. Can the controller be told to check both wires, wait a defined period and then check both again, and then output based upon comparison? Otherwise, it seems that the controller would interpret a brake signal anytime both signal wires are hot (every time the signal flashed it would revert to brake signal).
It seems that as long as both signal inputs were monitored by the controller, changing the status of the signal wire (adding signal after braking or vice-versa), could be adapted to by the controller. Is that wrong?
The controller is really where my heartburn is at with this project, as I know NOTHING about them.
For power, I was thinking I could run a separate dedicated power from an accessory fuse, so the controller would be supplied with 12v anytime the key is in the on or accessory position.
I’m pretty comfortable creating a container and weatherproofing. I’ve actually used RTV to seal wiring through pelican cases in the past with no negative consequences, and this enclosure would be mounted somewhere out of the elements as possible.