Why does Buzz "freeze" in the first film?

For most of the first movir Buzz thinks he is a real Space Ranger and that he’s human, but when ever a person is around he is in toy mode. But he thinks he’s real so why does he do it? The best thing I can think of he thinks they may hurt him cause there twice his size and he "Plays dead’.

I think its like toy intuition
Woody has been a toy for longer thus causing him to “break the rules”

Not really a right answer to this

Yeah, that’s one of those good questions about the film you don’t always think about. Here’s my theory:

When the Buzz Lightyear toys are in their boxes it seems like they’re already frozen in toy mode and then come to life when they’re opened thinking that they’ve awoken from Hyper-Sleep (then again you have The Prospector in Toy Story 2 alive in his box when he’s supposedly never been opened, but it could be something different for him entirely that’s unrelated to the way Space Ranger toys behave). And of course after Buzz tried flying out the window and broke his arm off he now had a reason to not feel like moving because he was broken out of his delusion and now thought of himself as just a worthless toy. I think the reason he did this in Andy’s room is because he assumed that it was something that the creatures of the planet (Andy’s toys) had to do around Andy (who he calls their chief) and that’s why he says that he was “accepted into their culture”, but maybe he didn’t think much of it since he was still wanting to fix his ship and wasn’t planning on staying anyway. I have noticed that all the times he’s done this in the film before he knew he was a toy were always with Andy and that from the gas station to Sid’s house he’s moving around in stealth the way he does as a Space Ranger at the risk of being seen by other people.

Probably the only parts in the film where this theory doesn’t seem to fit are the two scenes with Sid where he freezes when he spots him in the claw machine and then the next day when they’re in his room and he was torturing them. I’m sure Buzz had his reasons for not moving then, but when he first saw Sid in his backyard he certainly thought he could take him down.

I also know from playing the Toy Story Animated Storybook game that in the scene at the gas station Woody freezes into toy mode when a truck pulls up but Buzz just hides behind one of the pumps and watches.

I know I don’t have a lot to work with, but I can honestly say that it’s toy instinct. The script states that Buzz was FORCED to freeze once he was put into Sid’s view in the Crane Game. I guess the reason Woody and the mutant toys could move in front of Sid was they had to be aware of their instincts, and go against it.

The topic of when toys first come alive is another discussion on its own, but I may as well add my explanation. I think all toys come alive once they are finished, such as the prospector. Since Buzz Lightyears think they’re real, they are thought to be in hyper sleep, and continue their hibernation until they’re opened. Plus, it’s also known that a toy that’s alive can wake up a dormant toy from when the mutant toys woke up his buried toys.