Hard Brake Pedal 2015 ES350
 

So now this has happened a couple of days in a row. When I get in the car in the morning, the brake pedal is hard as a rock, no movement. As soon as I start the car, it depresses and feels normal throughout driving. If I start the car soon after turning it off it feels normal. It seems to be after a long (~8 hours) period of non-use.
I didn't know if there were any electronic actuators to adjust pedal travel or is it vacuum?

Any ideas?

Jim

Sorry, 2012 ES350

You may have a slow vacuum leak in your booster. It appears that when the car sits for a long time the vacuum goes away and you lose all assist making the pedal feel hard. When you start the car the vacuum comes back and it feels ok. Your engine will start running rough and CEL will come on when the leak gets bad enough. Get the vacuum checked and if confirmed change the booster.