Hi @dongali,I figured out the turn signal wiring!
The Grand Touring and Signature headlights require 2 constant 12v inputs for each side of the front turn signals which the Sport and Touring harness is missing.
What I did to test this theory was wire an always on 12v to the 2 wires- white/black wire and blue wire on the GT/Signature harness that I purchased, PN: TK50-51-0K6.
The wire color of the engine harness differs from the headlight harness. The white/black and blue wires on the GT/Signature harness connects to the Gray wire on the engine harness.
There is an always on 12v at position 50 in the engine fuse box, which was also originally for the hazard and front/rear turn signals.
Engine Fuse Box Diagram
Thanks so much for your post. Very interesting project. May you please tell me where you were able to find the PINOUT diagram for the wiring harness connector?
Also, is there a pinout diagram for the plugs on the headlight itself for the grand touring? It has two 7-pin plugs: one on the bottom and one on the rear. I want to test the LED DRL and the turn signal; but I have not been able to find which pins on which connector lights up the turn signals.
Please help. Thank you.