Took in my 2010 LEXUS 330 RX three tiems because it would not start. Had battery replaced - no improvement. Was told car had 'normal power usage' while sitting for a few days. 'Newer cars, all these elctronics, blah, blah.' BS! Actually, I only took the car in once msyelf, next my boyfriend and then my friend's husband. Made no difference.
Finally went to another LEXUS dealer and they discovered bad motor on rear lift door. Replaced (under warranty) and now problem is solved.
The attitude of the DESERT LEXUS people is one of 'Not an obvious problem, I don't care, so go away'. And I had bought my 2nd LEXUS (2010 model 450 H) from them just last year. Never again, you can be sure!