Noticed that when the keyless remote is pressed, to lock & arm, that only the divers side turn signals flashed. Normally all turn signals flash to alert alarm is activated.
Scanned FSM - EL Theft Warning System to see if this behavior was indicating something, didn't find anything yet.

When I repeated arming / disarming with remote I did get the passenger turn signal to flash once, out of sync, with drivers side signals one time. Could this be a symptom of simply a lighting relay sticking or going bad or possibly an issue with the Smart Entrance Control Unit?

The fob blinkies have their own DPDT relay separate from the hazard wiring, and one of the throws probably has bad contacts. It's at the front of the driver's side relay box next to the taillamp relay. See EL-380 here, connector E17:
https://www.nicoclub.com/service-manual ... 1%2Fel.pdf

Thank you. I need to refer to that page more often, got hung up on the ‘theft warning’ section.

After reading your post I confirmed operation / location by placing a finger on relay while operating remote and afterwards pressing hazard button on dash (relay not used). I then swapped the (working) 'rear-defrost' relay (identical part #er) to ‘key less’ (E17) location and all signal lights flashed again as designed.

Was about to order from NPD, but since removal of ‘key less’ E17 relay does not seem to disable any other function other than signal lights (when pressing remote), I wondered if the relay cover was glued on or just snapped on. The latter in this case was true and I was able to pop the relay cover off.

I checked coil continuity (good), promptly dropped it on the floor which tweaked the copper reeds, bent the snot out of them to realign (that’s its own thread), then cleaned contacts by dousing strips of paper in alcohol, slipping strips in between contact(s), gently pressing contact closed while pulling out paper strips, followed by electrical contact cleaner to wash anything away. I put a thin coat of silicone grease around plastic base where snap on cover is received to seal out any grime (or gaps created during popping off cover with small screwdriver)…. and success (so far), it works well again.

https://imgur.com/XjB1EjC

Those contacts have lost their plating, they're not long for the world. If you like to fiddle, a little capacitance like an old school condenser may keep them alive a bit longer by soaking up the arcing.

Got it. Then since there are other relays that share that identical part #er in there, I think I will order a spare, wrap it in plastic, and store it in one of the empty spaces between the other relays for back up.(sorta like the spares in the under-dash fuse panel)

Never hurts to have spare relays.