I believe it's 10 seconds, not two. Also, make sure that you are not holding the button all the way down to automatic. It is a two stage switch. Just hold it in the first stage. If that doesn't work, the reset procedure for the motor can be found here.
http://www.350z-tech.com/wiki/index.php ... _Procedure
Good luck.
Also, if you can't fix the problem, I found that this problem only happens with the auto up feature. If you use the manual mode to put it up, it won't come back down.