The following ONLY occurs during wet weather:
I have a 92 Honda Accord LX with automatic transmission. Starting
from a stop, the car feels as though it's trying to start in third
gear. Once we get going, I cannot seem to get it to go beyond third
gear. On the highway, I can't go past 50 mph, and the tachometer
stays around 3. I noticed that with the engine running and while at a
stop, if I shift into other gears, the D4 light on the dashboard
remains lit (i.e., if I shift to reverse, the R light and D4 light are
lit). The car moves in the correct direction while in the other
gears, but the D4 light stays on.

I think the Transmission Control Module (TCM) is bad, but I wanted to
get others' opinions. Is there a way I can test if the TCM is bad?
Do you have any other ideas of the problem?