Well, Kiddies, after a bit of poking about the turn directional now works. Has been working now for several days. As I was using a meter to read contacts, as part of this I added a temporary ground to the existing. As soon as I did, the turn directional started to work. Removed it, it still works. Temps have varied from below freezing to mid 60s, I don't think it is a poor ground.
I will assume not that the ground was bad but that the DDM possibly needed to learn it was there. I feel that when I added the second ground which was a heavier cable, the DDM saw a change in state. I had to reteach the DDM the passenger window Open and Closed states afterwards which is why I wonder if the DDM was involved.
Either way, it works.
Side rant- DigitalVoltMeters lie. They are like politicians. It depends on how you interpret their results whether you can trust them. DVMs use a very small current to read resistance. The older Analog meters with their fragile needle pointers use much more current and are much better indicators for testing contacts and wiring. As a tech working with low voltage wiring, telephone circuits, computer LANs and so on for decades, I have seen circuits test "good" that do not work as they cannot carry any current. With the proliferation of all the sensors and additional wiring and connectors, I often wonder if people are chasing symptoms of marginal connectors and/or bad harnesses and that is why replacement parts don't fix issues. Or identical issues return. Decades ago, the burglar alarm guys had "Peter's Meter" which wasn't really a meter, but a t-shoot unit that had a relay. As you went around trying to find a bad connection, the relay would latch the trouble indicator so that you could see it failed, even momentarily. You would insert it at the alarm panel and then could go through all the windows on various floors, stopping to check it every once in a while. When windows heated up back in the copper days, it was common for one window to develop a hairline crack. when it got cold, it would send a false alarm. I use my Fluke digital all the time but as soon as I come across something I stop to think about, if I can I use my old Simpson. It has saved me many days worth of troubleshooting and recalls. Wonder if I should create long leads with insulation piercing clips so I could then bypass the connectors. I did clean the DDMs pins earlier in my t-shooting.
Regardless, with the driver's side directional working, I also ditched the original passenger side with a turnsignal equipped one. Then moved into replacing dead lighting in the door switches, now moving into the dash. The only other issue is a broken actuator in the Heat/AC unit in the back. It will be a bit of time before I can tackle that one.
Thanks,
John