On a peaceful Saturday, my 3month old RX450h became inoperable with multiple confusing warning messages (see the pics below).
In the morning, the car ran perfectly, and I parked it in the outdoor parking during my business. 4 hours later, when I powered it on, it refused to move. I can switch the gears but the car didn't move by an inch as if the brake is locked up.
Eventually, I had to call AAA for towing to the Lexus dealership, and apparently the service manager has not seen this before either (luckily made it before the dealership closes).
The pics didn't show some other messages including
-a warning about low brake power (or that sort of)
-a warning about VCS

If you have seen this case before, I beg to share your experience. This has only 3300 miles on it, and I'm afraid this is some big issue that the dealership never fixes.
In any case, I will share back whatever I hear back from the dealership as soon as I can, so at least this can be helpful for some others.

 

I just found something similar in the threads: https://www.clublexus.com/forums/rx-...-starting.html
Is this a common thing in RX450h? Could it happen while moving the car??

 

Continuing my own update here. The related thread is here: https://www.clublexus.com/forums/rx-...tarting-9.html

The deal blamed the after-market-dashcam that I have installed for the issue. But, I didn't agree as it was properly tapped into the fusebox with a tapping wire (which has also its own fuse), in addition to another fuse to the camera. After taking off the camera and resetting the error code, still, the problem persists. Now, the vehicle is being looked at by their best technician and a Lexus field engineer(?) to identify the root cause. They suspect the electrical issue, which sounds very concerning. The vehicle is not still operable.

 

This is a known issue with Lexus 4th gen. My RX got a same errors at 10k miles. What I did is power off the car for 5 minutes, and press the brake down harder and start the engine. This happen once a while in the morning. I brought it back to the dealer and they are replacing 4 BRAKE BOOSTER ASSEMBLY.BRAKE BOOSTER WON'T HOLD VACUUM.

I hope this will help you!

 

@PETERPHAN8, did that resolve your problem once and for all?

 

Sounds like either the electric actuator responsible for pressurizing the system failed or the system is leaking somewhere (through the booster itself or through plumbing), thus throwing codes and preventing the car from being driven so it doesn't drive without assistance to the brakes. That would my guess. Theoretically, yes that would be bad if it failed while you were driving. I'd guess you'd still have brakes, but just very hard to press.

 

Finally, got the car back. The dealership found a fuse for the brake system and others was gone bad. They suspect the fuse-tap for the after-market dash-cam is related to this (as the broken fuse is right next to the tap). After the technician did the fuse tapping again, the problems don't come back. I hope this is not an intermittent short in a system.