Did my monthly maintenance run today of about 30 miles. After I parked the coach back in it's storage space and leveled it, (parking spot is almost level) remembered to check the transmission fluid level using the up and down arrow buttons. Got a readout of "d 1" that alternated with " - - ". I didn't find that in the transmission manual, but maybe I didn't look enough as I was in a hurry. I did take the time to check the fluid with the dipstick and it was normal, half way between hot and add. Someone must know what this means.
1996 was about the time the fluid level check became available. Yours doesn't sound like you have it, since with the fluid level feature, you have to hit the up/down arrows TWICE to get to the diagnostic codes (d-1 - - means no diagnostic codes).
If you had fluid level check, the first hit of the up and down arrows would bring up OL.
As Brett noted you may not have that feature. However, I would just ask if maybe you had a quick reaction and double tapped the up/down arrows to skip over the OL and directly into the diagnostics.
I've done that more than once -- being less than well-coordinated :D .
Your trans serial number a a call to Allison will tell you if you have it or not.
Thanks for the replies. After owning it 10 years, I think that was the first time I tried that. Maybe I do not have that feature. Pushing the neutral button would make it go away, and I would get the same thing the next time.
Our '93 definitely don't have it, but that's OK with me. I'm more of a dip-stick kind of guy, anyway. I like to actually see the oil on the end of the stick, check the color and the smell, drip it all over the ground and my pant legs and shoes. Tactile stimulation vs virtual reality...