I am installing exterior mirrors with LEDs tied to the blinkers.
I have read the service manuals and it looks like there aren't any blinker leads in the doors so I need to tap into the wiring harness.
Anyone done this before or am I the first one to tackle this?
I was thinking of running a signal wire from the front of the car, through the flexible conduit near the door hinges and up to the mirrors for each blinker side. I should be able to find a ground somewhere along the way.

 

That's one way to do it. To do this, I would pull off the front tires and remove the fender liners. You should have access to everything after you do that. If there is no power in there for the JDM fender markers, you can pull wire from the turn signal lead directly. Be sure to check for proper function first before cutting any wires.

One guy that did an M connected to the BCM inside the car.

I've never done this mod before but would be very interested in what you find under the fenders. Be sure to post your results!

 

I had considered messing around with the BCM. I found the wiring and pin outs for both blinkers and where they attach to the BCM. The Service manual is very clear on that one.
I haven't received the mirror covers from the vendor, they ship out today from Japan. Since they are LEDs, I should be able to run a small gauge wire. Possibly 20-22. That should help running it through the mirror chase.

I looked for side marker wiring in the manuals but I didn't have any luck. I won't know for sure until I dive in and look for wiring, possibly this weekend.

 

If I were one of the designers, I would put in a connector in the harness that can either be plugged directly into the fender markers on the JDM version or have a place in the main harness for a "pigtail" to plug into. That way the main harness can be used for both JDM and domestic models. The pigtail can then be a JDM part number.

 

I'll go diving with my dc test light this weekend.

I'll let you know what I find.

 

cool stuff. i want to follow the progress. I would love to have some as well.

 

It is Saturday and I finished the installation for the LED Signal mirrors. Terrycs. There aren't any wires under the fender liner. I removed the front left wheel and liner and no side marker wires or even a harness to the front.

I finally decided that the rear of the car was easier to get to than the front and firewall. I removed the trunk liner and ran both the ground and signal wires from each rear blinker from the trunk to the firewall area. It was by far the easiest path. Funny thing, the rear blinkers have their own ground and not a shared chasis ground. I determined this with my 12volt test light. It would not light up on the hot signal when the test light was grounded. My only solution was to run both signal and its ground up to my mirrors. It worked great!
There is a free and easy to get to path under the door sills but I had to remove the rear seat to run my wires.
It took almost 6 hours but I could do the next set in 2-3 hours from what I learned.