I have a 2005 lexus gx470 and about 70 % of the time when I want to make a phone call or navigate the touchscreen will not let me access it. Any ideas on how to fix this?

 

Are you moving at the time?

Many functions are disabled while moving. Bypassing this is not trivial. Some functions require you to be stopped, some functions require you to be in Park, and some functions require the emergency brake to be applied, before they will work.

There is a temporary override though, which only works until the next time you turn the key off:

Press Menu.

Press Volume.

Press top right corner of screen.

Press bottom left corner of screen.

press top right again.

press bottom left again.

press them one more time.

A diagnostic screen will appear. Press and hold the "Override" button until you hear a beep.

Now the nav functions will work while moving.

I use the above trick all the time so the passenger can use the system while I'm driving.

 

^^^ nice info ...thanks ^^^