95 Lexus ES300 No Overdrive

Hey!
Got a 1995 Lexus ES300 Cal emissions vehicle, 214,000. Engine VERY strong. Started having intermittent bouts of the overdrive not kicking in. Overdrive light and switch is good. There are no codes/ CEL. (yes, the bulb is good) No flashing OD light.It has become more of a permanent issue as of late. Trans fluid and filter changed…made no difference. Any ideas?
Vehicle shifts smoothly and perfectly in all gears…it just no longer shifts into OD.
Thanks for any help.
Another WEIRD thing was that the ETC POWER light comes on when the headlights are turned on. Strange.