Test PCS Pre-Collision System, not working
 

I feel that my PCS (Pre-collision system) is not working.But with my ES 350, I just could not make it beep at all, even after set the sensor to the most sensitive level. Wonder if anyone tested it. Does it use front camera? I I will definitely go back to dealer again, but not 100% sure about the PCS.

What makes you feel as though it's not working? PCS uses radar to detect objects and people and uses the camera to verify.

You really shouldn't be testing this out yourself as it is designed for real-world use and not homemade testing as it can be quite dangerous. Should you be testing it under circumstances it is not actually designed for, you risk damaging your car and will be completely liable for all damage.

That said, I'm guilty of it too and have tested it out myself with success and have experienced it in real-world action as well & am quite familiar with how these systems function. Please go into detail with your testing method and I can try to help determine whether or not your tests were flawed or if there is in fact something wrong.

It just compering my old 2018 honda ,lexus it just like not sensitive at all! i did drive close to cars it not responding!

its all green bars

It's not about how close you get to other cars but rather how quickly you're approaching them. This is intentional as the system is designed to be as minimally intrusive as possible, which I've found to be the case. Lexus engineers did an incredible job tuning the system to only warn you and/or intervene with autonomous braking when you actually need it. You're likely to never experience false positives, it's a very good system.

Can't really intentionally set it off. Probably need to drive 40-50 mph to a stationary object to see if it works.

But as I drive, it will work when I need, such as the car in front brake abruptly.

I mean this in the nicest way possible but this is unsafe and poor advice and exactly why we're not supposed to try and test these systems ourselves. These systems have limitations. At around the 45 mph mark, the system WILL NOT BE ABLE TO DETECT STATIONARY OBJECTS. IT WILL NOT WARN YOU. IT WILL NOT STOP.

Green bars? Are you talking about PCS or are you talking about parking assist?

thank you for all the replies. I was on the way to the dealership and tested it a different way than my Honda. With my Honda when I accelerated too close to another car then it began beeping. With Lexus it works a little different, if you come close to another car and your foot is not on the gas pedal then that is when it begins to beep.

There are videos at www.lexus.com that describe and illustrate all the Lexus Safety System features: Automatic High Beams,
Pre Collision System, Lane Keep and Lane Trace Assist. It is easy and safe to demonstrate the low speed Auto Braking that
uses the Park Assist Sensors (dime sized circles) on the front and rear bumpers but it is unwise to dynamically (and dramatically!)
test the high-speed PCS. PCS uses both the camera but more importantly the millimeter radar sensor behind the Lexus Arrowhead
on the front grille. I have had the system warn me once when I was going 35-40 and the car ahead abruptly slowed to turn right.
We were about two car lengths apart and the radio muted, the system squawked and the entire Driver's Information Center between
the Speedo and Tach lit up Red with BRAKE! in white. I tapped the brakes but from the video I believe it would have intervened
if I had not.

I agree with the others who are saying that there likely is no safe way to test to see if the system is working properly.

If you think about it, it is really remarkable technology that allows the system to warn the driver or automatically brake when it is appropriate to do so and that doesn't warn or brake when there is no need to do so. And I think that the technology has improved quite a bit over recent years. A few years ago, I recall reading posts here from people who reported that their cars were braking when they were crossing bridges or changing lanes. My 2017 ES is my first car with such a system. During the 2+ years that I've owned it, it has warned me and braked 1 time, and, when it did so, it was appropriate. It has not given me any false warnings or braked when it should not have done so.

Also, I'm sure that the car's computer does regular periodic checks to confirm that the system is, in fact, prepared to function properly, and, if any of those checks fail, you would be getting warnings on the instrument cluster letting you know that there is a problem with the system.

Yes not to say yours may not have an issue , but they are pretty smart systems with many systems checks when the car is first started .
it is a preety smart system being able to detect what is and isnt a potential threat,as Signdatres has noted I too have had the giant red Brake warning come on on me w someone abrubtly braking and turning in front of me, though i was paying atention and could brake safely on my own , it def proved helpful if you were even slightly distracted for examlpe.
I have also had the auto braking function activate when backing up , i was backing up to a rubber cone , it wouldnt let me even slightly tap it before it activated the brakes . ( funny the ABS pump was so loud i thought at first i hit something) .lol
the other time i wa backng from a parking space , was warned by the monitors a car was aproaching , i was stopped actually , but the guy passed by me so close to my rear bumper it activated the brake pump even then. I guess in the event i were to remove my foot from the brake.
Short story long... i think thier system is one of the better ones out there esp w the settings that you can taylor for some actions.

Every time I pull into my garage the sensors go crazy. Sounds like impending doom. Front and side sensors aren't happy. The ES is longer than my previous vehicle by 4 inches! So I have to inch forward slowly. It's kinda of nerve wracking. Maybe I might have to buy a new house with a larger garage. :yikes:

Are you talking about the parking sensors or the pre-collision system warning? When the corners of the car are within a short distance of any part of the garage or anything within the garage, the parking sensors should be alerting you, but the pre-collision warning, which is the topic of the OP, should not be doing anything.