'95 3.0 Auto trans

This just started happening this weekend on the Big Bear trip. I put the shifter in low but the trans will not stay in low. It behaves as if I'm in drive. Same thing happens if I'm in 2nd.

Fluid level is fine. the "OD off" button works as it should on the highway. I had someone move the shifter while I watched the little arm on the trans that's hooked to the cable. It moves fine.

The lights on the dash that tell what gear I'm in don't light up. I wonder if this an indication that somethnig came disconnected.

Over the summer I took the T-case out and put it back in but everything worked after that on the Sierra Trek.

Any ideas?

-Kirk