Here is the deal, when i bought my GS the previous owner had after market signals on it. Not only were they ugly but he chopped the harness all to hell putting them on.
I have replaced all 4 signals and the right turn signal works good, but the left not so much. The rear was east but the front was a rat's nest of wires. He had 3 different wires hooked up for it to work properly and when i was changing the signals out I got them mixed up.
Could someone take a picture of their left from indication wiring so i can trace those wires and get my signals working? I have a 2001 GS500E if it makes a difference.
I have looked at the wiring diagram on the wiki but that wasn't any help. I couldn't find any of the wires it was talking about.
You might have the best luck just taking a multimeter to it. If the PO whacked at the harness enough, it might not be anything like anyone else's. Just turn it on, turn on the turn signal and start checking for voltage on the wires you think might be the right ones. Eventually you'll find the one that is flashing on and off... If there are only three wires, it should only take you a few minutes to figure it out...
Have you sorted this out yet?
There is a simplified wiring diagram with wire colors.