Had the trans warning light pop on after a 20mi run. Parked, did an errand, back in the car and started it up noticing no light. Drove back and stopped again for an errand with the light back on. Of course, it "bump shifts" when light is on. Checked fluid level back in the garage before shutting it off. Fluid level well above "hot" range. Checked fluid level later that night when car was cold. Fluid level was the same as when "hot". Fluid doesn't smell burnt and is good color. A complete trans service was done 2 years ago, including an additive to trans fluid due to high-mileage (210K+) of car. Car is 92/93 4.0 convertible.
I'm stumped...any suggestions?

 

I can't help but I'd like to know the answer to this one.

 

Just to confirm, the engine was running during both tests, hot and cold? At cold test, with engine running, you had shifted through all of the stops, then back to P?

 

Engine running after driving 40mi when I checked the stick 1st time. So, 1st check was a "hot" check. Several hours later, 2nd check was not running to see what "cold" check would show. I just did "cold" check in garage with engine running and ran thru gears. Fluid level seemed correct this time and no warning light. Going to take it for a run later today and do another "hot" check.