In preparing my RL to be sold I was going to trade my 4.64 dvd with someone who has a 4.13. I successfully downgraded my dvd but when we put the newer one in his car his navi just keep rebooting. So I gave him is 4.13 back and put in the 4.64 and now mine just keep rebooting. The screen comes up and says acura navigation then black, then acura navigation, every 10 seconds. Does anyone know how to fix this?

Background
I upgrade from 4.13 to 4.3x in 2007, then to 4.5x in 2008, and 4.64 in 2009.

 

For his car, at 4.13, without interim upgrades, I believe 4.64 needed a second disc from Alpine. What you should do is take your other discs and upgrade him from 4.1x to 4.3x to 4.5x to 4.6x....or call Alpine and get the second disk.

Cannot say what happened to your car, except possibly the same thing. If you reflashed back to 4.13, then going straight to 4.64 will not work without the second disk. You likely need to do the same thing and go from 4.13 to 4.3x to 4.5x to 4.64.

 

I think this is all fixed with 4.7x and 4.8x