I found this one the www.hondacarforum.com
You have a couple of choices on this Honda transmission... D and S modes. Consider the D as the normal Drive mode and the S for Sport mode. The difference between the two is that in "D", the transmission will shift through the gears all the way to 4th gear and at lower rpm shift points. In "S", the transmission will shift at higher rpm levels and will go no higher than 3rd gear and light S3 on the dash. Once the vehicle is in 3rd gear (S3) you can then press the S4 button and the transmission will go into 4th gear (when conditions dictate). I believe there is even an S4 indicator on the dash signifying the trans is in 4th gear
The last line looks like it is the key here though.
If the car thinks its in 4th gear when you are trying to start it, obviously it wouldn't start...you could probably hunt around and see if there is a sensor on the transmission stick that runs the "D" vs "S" mode