I don’t really know if my problem existed before, but I installed a solid state turn signal relay. The arrow lights on the dash now blink when the turn signals are on. I noticed that for the left lane change position the light didn’t blink but did come on solid like with the old relay. I thought that was suspicious since for full left and right and right lane change, the dash lights now blink. What I found was that the outside lights weren’t coming on in only this one left lane change position. I haven’t started trying to track down what might be wrong with the wiring schematics. Can anyone save me some time?
I noticed a similar problem on my '70 Cougar while developing the LED sequential controller. When I compared the connections to a new switch, the turn signal switch was not making both internal connections (front and rear lights) simultaneously in the lane change mode. Verify this by using a self-powered test light to check the connections in the lane change position after unplugging the switch. I noticed that it depended on how close to the detent you pushed. On a tilt switch, the cam can be removed and some of the excess grease removed. On a non-tilt switch, the rivet must be drilled out and a hole drilled/tapped to replace the cam. Unfortunately, it may require replacing the turn signal switch to solve the issue if the switch contacts are worn.
Thanks for the info. Glad to know where to start and that it might be a relatively easy fix.