He was exhausted and frightened after having so many cars go whizzing by him at 60+ MPH. As soon as he got across the road he went under the nearest bush where it looked like he went to sleep.
Surprisingly though, at one point when I was photographing him he walked right up to me, probably only 2 feet away or so before I slowly backed off. I was shooting with my 70-200 lens but had the closeness selector on the lens set to the longer distance and couldn't get focus on him any longer. And he definitely knew I was there. Was a really cool experience for my first tortoise encounter (and I've been in and out of the Mojave for over 35 years, so it was a real treat).