I just purchased a 2006 S with 6 spd auto this week. Twice now while I was driving the car would not go into "SD" mode. If I moved the stick over to the sport mode, the display remained "D" and it did not perform as it should in sport mode. Also if you use the paddles to shift during this problem, it would shift as you requested, but after 5 seconds it goes back to "D" and changes gears how it wants. The cure for this is to turn the car off and restart it, and it's back to working properly. But in only 4 days of ownership this has happened twice. I am guessing it must be a computer problem, but what is the fix for this? Would aftermarket trans software ekiminate this issue? Is there a seperate computer for the transmission or is it in the main ECU?

 

If you use the paddles to shift during normal transmission mode, it is supposed to go back to Normal driving mode after several seconds. That's how it is designed. It's good when you are just driving in normal mode, but come up to a corner and want to downshift without going into Sport Mode or into Manual. It allows you to slow the car using the transmisison instead of breaks, go through the corner, and then go back to normal driving. I use it all the time. I can't answer the question of why the car won't go into Sport Mode for you, that's a different issue. Good luck.